Characterization of Solar X-Ray Response Data from the REXIS Instrument Andrew T. Cummings

Characterization of Solar X-ray Response Data from the REXIS Instrument by Andrew T. Cummings Submitted to the Department of Earth, Atmospheric, and Planetary Sciences in partial fulfillment of the requirements for the degree of Bachelor of Science in Earth, Atmospheric, and Planetary Sciences at the MASSACHUSETTS INSTITUTE OF TECHNOLOGY June 2020 ○c Massachusetts Institute of Technology 2020. All rights reserved.

Author...... Department of Earth, Atmospheric, and Planetary Sciences May 18, 2020 Certified by...... Richard P. Binzel Professor of Planetary Sciences Thesis Supervisor Certified by...... Rebecca A. Masterson Principal Research Scientist Thesis Supervisor Accepted by ...... Richard P. Binzel Undergraduate Officer, Department of Earth, Atmospheric, and Planetary Sciences 2 Characterization of Solar X-ray Response Data from the REXIS Instrument by Andrew T. Cummings

Submitted to the Department of Earth, Atmospheric, and Planetary Sciences on May 18, 2020, in partial fulfillment of the requirements for the degree of Bachelor of Science in Earth, Atmospheric, and Planetary Sciences

Abstract The REgolith X-ray Imaging Spectrometer (REXIS) is a student-built instrument that was flown on NASA’s Origins, Spectral Interpretation, Resource Identification, Safety, Regolith Explorer (OSIRIS-REx) mission. During the primary science observation phase, the REXIS Solar X-ray Monitor (SXM) experienced a lower than anticipated solar x-ray count rate. Solar x-ray count decreased most prominently in the low energy region of instrument detection, and made calibrating the REXIS main spectrometer difficult. This thesis documents a root cause investigation intothe cause of the low x-ray count anomaly in the SXM. Vulnerable electronic components are identified, and recommendations for hardware improvements are made to better facilitate future low-cost, high-risk instrumentation.

Thesis Supervisor: Richard P. Binzel Title: Professor of Planetary Sciences

Thesis Supervisor: Rebecca A. Masterson Title: Principal Research Scientist

3 4 Acknowledgments

I conducted my work as a research assistant with the REXIS program in the Space Systems Laboratory as a student in the MIT Department of Earth, Atmospheric, and Planetary Sciences and the MIT Department of Aeronautics and Astronautics. I owe this thesis to the dedication of countless friends, loved ones, faculty, and staff. Though there are too many to list, I wish to acknowledge a few: First and foremost, I would like to express my gratitude to Dr. Rebecca Mas- terson for her guidance and encouragement in the past year. Thank you for always challenging me to grow and improve as an engineer, and for always believing in me. I would like to thank my other advisor, Professor Richard Binzel, who first invited me to join the REXIS project, and whose passion for science motivated me to dream big and start down this road. Thank you for recognizing something in me, and for agreeing to advise just one last time. Additionally like to recognize the Harvard- Smithsonian Center for Astrophysics team of Dr. Branden Allen, Dr. Daniel Hoak, Dr. Jaesub Hong, and Professor Jonathan Grindlay for mentoring me. Many thanks to the REXIS cohort of Maddy Lambert, Carolyn Thayer, and David Guevel; I would do it all again for the laughs and camaraderie. Special thanks to Megan Jordan for tolerating endless paperwork and logistics, and at times, wrangling me in. I would also like to thank my family for sending their love and support from so very far away. And to my friends: Lucy, Dan, Brandon, Ruth, Brendan, and Lara; Thank you for being the people who lifted me up when I was down, and for being with me all the way. Lastly, I wish to thank the Halperin family, for welcoming me into their home during an unprecedented global crisis.

5 6 Contents

1 Introduction 13 1.1 REXIS Mission ...... 14 1.2 REXIS Operational Timeline ...... 16 1.3 Anomaly Resolution during the OSIRIS-REx mission ...... 17 1.4 Motivation ...... 18 1.5 Thesis Roadmap ...... 19

2 Background 21 2.1 Basic Circuitry ...... 22 2.1.1 Common Components ...... 22 2.1.2 Operational Amplifiers ...... 25 2.1.3 Signal Amplification ...... 27 2.1.4 Analog-to-Digital Signal Conversion ...... 29 2.1.5 Thermal Impact on Circuitry ...... 30 2.2 SXM Overview ...... 31 2.3 SXM Data Pipeline ...... 32 2.3.1 Instrument Response Modeling ...... 32 2.3.2 Chianti Atomic Database ...... 32

3 SXM Design and Operation 33 3.1 SXM Design Background ...... 34 3.1.1 Mission Requirements ...... 35 3.1.2 Overview of SXM Signal Amplification Chain ...... 37

7 3.2 Instrument Testing ...... 42 3.2.1 Ground Testing ...... 42 3.3 Flight Operations ...... 45 3.3.1 Early Flight Operations ...... 45 3.3.2 Flight Operations during Orbital B ...... 46 3.3.3 Flight Operations during Orbital R ...... 47

4 SXM Root Cause Analysis 51 4.1 SXM Low Count Rate Anomaly ...... 52 4.1.1 Orbital B ...... 52 4.1.2 Orbital R ...... 54 4.2 Constraining the Problem ...... 54 4.2.1 ISA #10939 ...... 55 4.2.2 Modeling SXM Instrument Response ...... 60 4.3 LTSpice Simulations of Amplification Chain ...... 61 4.3.1 Thermal Variability in Components ...... 62 4.4 Root Cause Next Steps ...... 65 4.4.1 Identification of Vulnerable Components ...... 65 4.4.2 CAST Analysis ...... 65

A SXM Circuit Schematics 69

B Simulation Code 103 B.1 SXM Simulated Instrument Response Code ...... 103 B.2 SXM Histogram Rebinning ...... 107 B.3 LTSpice Simulation Readout ...... 114

8 List of Figures

1-1 Schematic of the REXIS Instrument and SXM (shown to scale). . . . 15

2-1 The symbol used to represent a resistor in circuit diagrams...... 22 2-2 The symbol used to represent a capacitor in circuit diagrams. . . . . 23 2-3 The symbol used to represent a diode in circuit diagrams. The positive terminal is to the left, and the negative terminal is on the right. . . . 24 2-4 A generic op-amp. (1) Inverting input, (2) Non-inverting input, (3) Positive power supply, (4) Negative power supply, (5) Output. . . . . 25 2-5 A generic op-amp with open-loop gain...... 26 2-6 A generic op-amp with closed-loop gain...... 27 2-7 An example differentiator circuit...... 28 2-8 An example integrator circuit...... 28 2-9 An integrator circuit with an additional resistor added to the feedback loop provides a discharge path for the capacitor...... 29 2-10 An example Schmitt Trigger...... 30

3-1 The REXIS Requirements documentation flow from Jones, 2015 [6]. 35 3-2 SXM detector and preamp housing. The SXM detector is located below the collimator...... 38 3-3 Schematic of SXM Amplification Chain. Outputs outb and outu are seen on the far right...... 39 3-4 SXM Trigger Circuit Schematic...... 40 3-5 SXM signals at various points throughout the amplification chain. . . 41

9 3-6 SXM Histogram of Ground Calibration Source. A strong iron line can be seen at around 200 ADU...... 43 3-7 Results of SXM Oven Test, November 2015...... 44 3-8 Temperature Fluctuations during the MEB Thermal Characterization Test...... 44 3-9 Ground Testing results of MEB susceptibility to temperature fluctuations...... 45 3-10 SXM Event Rate Histograms during L+30 ...... 47 3-11 SXM Event Rate Histogram from Orbital B, 25 July 2019...... 48 3-12 SXM Event Rate Histogram from Orbital R, 13 November 2019. . . . 49

4-1 Example Fishbone diagram used to outline a Root Cause Analysis. Each bone is used to categorize the type of cause...... 51 4-2 SXM count rate histogram from launch to Orbital R...... 53 4-3 SXM Saturated Histogram (Right) and Corrected Histogram (Left) . 54 4-4 SXM count rate histogram on 18 November, 2019. The gap in the histogram is when the instrument was not recording data, and is unrelated to the low count rate anomaly in Orbital R...... 55 4-5 Fishbone diagram constructed for OSIRIS-REx ISA #10939 . . . . . 56 4-6 Flare Coincidence between the SXM and GOES15...... 57 4-7 SXM longterm HV for its operational lifetime...... 58 4-8 SXM Temperature Phase Space...... 59 4-9 SXM Histogram Rebinning. The boxed area surrounds the SXM’s main signal peaks. The peaks at the outer edges of the figure are instrument artifacts...... 61 4-10 The SXM Signal Amplification Chain...... 64

10 List of Tables

3.1 Quantum Efficiency Requirements for the SXM Detector. . . . . 36 3.2 SXM Level 3 Requirements...... 36 3.3 SXM Level 4 Requirements...... 37

11 12 Chapter 1

Introduction

This thesis is intended to provide an overview of operations involving the REXIS Solar X-ray Monitor (SXM), and an investigation into the cause of unanticipated low solar signal seen during data collection. The SXM is a subunit of the REgolith X- ray Imaging Spectrometer (REXIS), which is mounted aboard NASA’s OSIRIS-REx mission. REXIS an instrument intended to use to produce elemental abundance maps of the surface of the asteroid 101955 Bennu, a C-type near-Earth asteroid using spectrom- etry. Bennu is of particular interest because it has a 1-in-2700 chance of impacting Earth between 2175 and 2199 [9]. The SXM is a low-cost, high-risk payload. Isolating the root cause of the malfunc- tion and identifying critical components that resulted in failure will provide future projects with additional knowledge for instrument design. The SXM works in con- junction with the REXIS spectrometer to characterize high-energy solar x-ray flux. The SXM is used to detect variable input from the Sun, which is used by the REXIS spectrometer to calibrate x-ray input to Bennu. This thesis will provide an explanation of how solar x-rays are captured by the SXM and how signal data are interpreted. Solar spectra analysis and solar temperature fitting techniques are discussed, as well as the limitations of SXM modeling. SXM hardware is explained, with a focus on the analog signal amplification chain. An operational timeline of the SXM will be presented. The focus of the latter por-

13 tion of the thesis will be on a root cause analysis of the low x-ray count-rate anomaly that occurred late in the SXM’s operational lifetime. This thesis will conclude with a roadmap for future work, including a more complete root cause investigation into thermal sensitivity, and a CAST analysis to highlight organizational and programmatic controls that may have contributed to the drop off in x-ray counts.

1.1 REXIS Mission

REXIS is a student experiment developed initially as part of the 2011 undergraduate capstone class in the Department of Aeronautics and Astronuatics at MIT. Construc- tion and management of the instrument was conducted in the MIT Space Systems Laboratory (SSL) as part of a larger collaboration with Harvard College Observatory (HCO), the MIT Department of Earth, Atmospheric, and Planetary Science, the MIT Kavli Institute (MKI), MIT Lincoln Laboratories, and Aurora Flight Sciences. Day- to-day operations and engineering are conducted primarily by students with guidance from senior faculty and staff including Professor Richard Binzel, the REXIS Instru- ment Scientist, Professor Jonathan Grindlay, the REXIS Deputy Instrument scientist from HCO, and Dr. Rebecca Masterson, the REXIS Project Manager, from the MIT Department of Aeronautics and Astronautics. To date, over 80 students have worked on REXIS at all levels and stages of the project. The REXIS main spectrometer relies on coded aperture mask spectroscopy to capture incident x-rays from Bennu’s surface in the soft x-ray band (0.5-7.5 keV). A total x-ray spectrum is derived from the soft x-ray data and REXIS was designed to detect, if measurable, signals from Si, S, Mg, and O. REXIS has two operating modes: Imag- ing and Spectral. In imaging mode, REXIS maps specific abundances to locations on Bennu’s surface with necessary spatial resolution at an observation distance of 700m. In spectral mode, REXIS records x-ray energies and produces the global average of the x-ray spectrum passing through the coded aperture mask. REXIS performs its science objective in concert with the other OSIRIS-REx instruments. The flight schematic of REXIS is shown in Figure 1-1. The primary components

14 of REXIS are housed in the main instrument. These consist of a 2x2 array of CCD’s housed within a coded aperture mask. Housed separately is the Solar X-Ray Monitor (SXM), which will be the focus of this study.

Figure 1-1: Schematic of the REXIS Instrument and SXM (shown to scale).

The SXM is an x-ray detector located on the outside of the spacecraft bus, so that it would be sun facing during observations of Bennu. The SXM is connected to REXIS by a coax cable, and SXM data processing occurs in the main REXIS instrument. REXIS is the second student experiment to accompany a New Frontiers mission as part of NASA’s education and public outreach initiative. The first student instrument, the Venetia Burney Student Dust Counter (VBSDC, formerly SDC) built by University of Colorado Boulder, flew on the New Horizons spacecraft and recorded interplanetary dust from between 2.6 and 15.5 AU [13]. REXIS is a significant leap in complexity from the VBSDC, and at its inception was required to "directly engage students at the undergraduate and graduate levels in the conception, design, imple- mentation, and operation of space flight instrumentation. (2011 internal program

15 level doc.)"

1.2 REXIS Operational Timeline

This section will discuss the operational lifetime of REXIS and the SXM, from its launch on 8 September 2016 until the instrument’s planned shutdown following the OSIRIS-REx Orbital R mission phase in November 2019. A more detailed explanation of SXM operations can be found in Chapter 3. Henceforth, some operational times will be referred to as "L+", which stands for months after launch, unless otherwise specified. For example, events in the L+30 phase of the mission occurred 30months after launch. The REXIS timeline is inherently linked to the OSIRIS-REx timeline. REXIS was powered on during L+14 Days for a payload inspection and functions check. The SXM took 3935 seconds of x-ray data, and the instrument function was nominal. The SXM was turned on for an additional function check at L+6, where the instrument threshold was set. A third functions check was conducted during L+18. The SXM remained nominal, and there were no anomalies in x-ray detection. The next big milestone was the L+22 Checkout in July 2018, where REXIS and the SXM were again checked for behavioral anomalies. Data collected by the SXM demonstrated full functionality. During L+22, REXIS was internally calibrated to identify background noise and hot pixels. As a diode detector, the SXM cannot have hot pixels in the same way as a charge-coupled device (CCD) detector. REXIS performed its cover opening operation in September 2018. The radiation cover was released using a frangibolt, after which REXIS detectors were first exposed to the space environment. REXIS underwent a series of cosmic x-ray calibrations (CXB), and the REXIS spectrometer was shown to be sensitive to stray light. The L+30 Calibration was the first time Bennu was observable in the REXIS field of view. During this calibration, a hot pixel mask was tested on REXIS. SXM count rates were lower than previous observations, but returned to previously seen levels in later flight. During flight, REXIS underwent a series of calibrations using the Crab Nebulaand

16 Scorpius X-1 (Sco-X-1), two known cosmic x-ray sources. Using a known, stable x- ray emitter provided a source that allowed the gain and offset of the REXIS detector nodes to be set. Crab Calibration took place in November 2018 and March 2019, while Sco X-1 occurred later, during Mask Calibration. Orbital B, the first REXIS observation phase, occurred from 1 July to 6 August, 2019. This was initially the only observation window for REXIS. The OSIRIS-REx spacecraft was placed in a stable orbit one kilometer above the surface of Bennu. The SXM count rate saturation anomaly was found during Orbital B, where the instrument reported abnormally high counts on the detector. On 5 July, SXM data was saturated with an additional value of 34880. It was believed that a "bit flip" occurred, where radiation moved the reset value on the SXM. This was corrected with a reset command from the ground. Additionally, throughout Orbital B the SXM began showing a two order of magnitude decrease in x-ray signal disproportional to the spacecraft’s solar distance. The results from results from the SXM’s Internal Calibration are depicted in Figure 4-2. More on this anomaly can be found in Chapter 4. In all, two anomalies were detected in the SXM, and three were detected in REXIS. For more information on REXIS anomalies, consult Maddy Lambert’s thesis [7]. Orbital R was the final observation window for REXIS, which occurred during November 2019. The REXIS team petitioned for, and was awarded, this additional observation to supplement limited data taken during Orbital B.

1.3 Anomaly Resolution during the OSIRIS-REx mission

Anomaly detection for instruments on OSIRIS-REx was primarily the job of the engineers and scientists behind the individual instrument. Generally, a few weeks were allotted after reporting the anomaly to conduct an investigation, and isolate the root cause.

17 After an assessment had been made, the instrument team would present a recommendation for how to proceed with using the instrument to the OSIRIS-REx PI. This recommendation included an identification of the incident, current results ofthe investigation, and conclusions about future instrument performance and how it might affect the spacecraft. The investigation could be closed without reaching adefined root cause, so long as the incident was isolated and did not impact other instruments on the spacecraft.

1.4 Motivation

Low-cost, high-risk spaceflight missions granting better accessibility to space than ever before. The REXIS project was developed with the philosophy of being a student instrument. From its inception as the final deliverable for 16.83, the MIT Aerospace Engineering senior design capstone class, where undergraduate students worked side- by-side with experienced research scientists and engineers. Students directly applied s learned in their undergraduate curricula, and produced an instrument of complexity, scale, and mission worthy of being included on a New Frontiers spacecraft. Like all projects, there were challenges faced along the way. A rotating ensemble of students created a challenging environment for informational and experiential entropy.

The REXIS instrument is categorized as a NASA Risk Class D mission, which is characterized by lower cost and the use of legacy hardware [11]. Indeed, a portion of the electronics design process for REXIS consisted of utilizing existing schematics from NICER, an x-ray instrument developed by the MIT Kavli Institute (MKI). These schematics were simplified for the design of the SXM as a matter of reducing cost. Identifying the source of the SXM spaceflight anomaly not only provides guidance on potential hardware vulnerabilities which exist in current spaceflight missions; it also yields a roadmap for future missions.

18 1.5 Thesis Roadmap

This thesis is organized into six chapters, which document the SXM background, instrument anomaly, and subsequent investigation. The current chapter has intro- duced the larger REXIS mission, operations over its lifetime, and how anomalies were identified, catalogued, and solved. Chapter 2 presents a background onthe SXM, including an explanation of the SXM data pipeline and associated solar x-ray modeling. A broad overview of the electronic components that comprise the SXM will be provided, as well as how they operate in the space environment. In Chapter 3, the structure and design process of the SXM will be explained in greater detail. This is followed by a summary of instrument testing that occurred, both on the ground and after launch. Then, SXM flight operations leading up to and after the anomaly are discussed. Chapter 4 explores the SXM root cause analysis. The identification of the low count-rate anomaly is explained in depth. The investigation into the SXM pre-amplification chain electronics is next. The chapter ends with a plan for future research into the identification of the vulnerability that caused the anomaly andhow such a finding may be interpreted.

19 20 Chapter 2

Background

This chapter will describe the circuitry used in the SXM. The SXM relies on an intricate array of amplifiers and filters, which are capable of x-ray detection when combined. The chapter will begin with an introduction of standard electrical components and how they operate. An example circuit of each component is provided and includes a visual representation of ideal operation. This will create a foundation of understanding that will translate to more complex electrical engineering systems seen in the SXM. The first advanced concept explained is signal amplification. Signal amplification is the primary means through which a signal is passed from theSXM detector and recorded by the instrument. Typical amplification techniques will be compared against amplification used in the SXM. To understand signal processing in the SXM, an explanation of analog-to-digital conversion is provided. A more thorough model of SXM signal processing is covered later in the chapter. The thermal sensitivity of electrical systems is explained, and typical response sensitivities are modeled. An overview of the SXM will explain the functions of the instrument in broad terms. The SXM Data Pipeline will be explained from end-to-end. A theoretical solar x-ray response will be followed from detection, through the pipeline, and finally to transmission to the ground. Finally, the chapter concludes with theoretical instrument response using the Chianti Atomic Database and an explanation of how it was implemented in the Data Pipeline. SXM instrument simulation code can be found in Appendix B.

21 2.1 Basic Circuitry

This section introduces the common electrical components used in the SXM, how they operate individually, and how they are used together to create more complex circuitry.

2.1.1 Common Components

Resistor

Figure 2-1: The symbol used to represent a resistor in circuit diagrams.

A resistor is an electrical element with a positive and negative terminal that utilizes the property of electrical resistance. Its primary functions include voltage division, current flow reduction, and signal reduction. Ideal resistors function based onOhm’s law, 푉 = 퐼푅 (2.1) where the voltage differential across the resistor is proportional to the product of current and resistivity. Resistors are commonly used in two constructions: parallel and series. Resistors in parallel are be treated as the multiplicative inverse of the sum of the reciprocals of individual resistors,

1 1 1 1 = + + ... + . (2.2) 푅푒푞 푅1 푅2 푅푛

Series resistors are treated as the sum of individual resistances,

푅푒푞 = 푅1 + 푅2 + ... + 푅푛. (2.3)

. In practical application, resistors are susceptible to series induction and parallel

22 capacitance in alternating current (AC) systems. These vulnerabilities are expressed primarily in the high frequency regime, which can impact signal amplification. Re- sistors are thermally emissive as a property of power dissipation. Power dissipation in an ideal resistor is modeled as

푉 2 푃 = = 퐼2푅 = 퐼푉. (2.4) 푅

This power is converted to heat and emitted by the component.

Capacitor

Figure 2-2: The symbol used to represent a capacitor in circuit diagrams.

A capacitor is a passive, two terminal component that stores electrical charge. When a voltage potential is passed along a capacitor, an electrical charge is produced. A capacitor consists of two charged conducting nodes separated by a non-conductive medium. This medium consists of either a vacuum or a dielectric material, which can increase the capacitance of the component. Capacitors are characterized by their capacitance. In an ideal capacitor, its capacitance is measured as the ratio of charge held to the voltage across the component. This is represented in the formula

푄 퐶 = (2.5) 푉 in a DC system. In AC systems, a capacitor’s impedance influences the capacitance of the system. Impedance can be considered as a vector quantity described as the sum of the resistance and reactance, which is the component’s opposition to current. Impedance is inversely related to capacitance and signal frequency. The characteristics of capacitors in parallel and series are exactly opposite of a resistor. The capacitance of multiple capacitors in parallel are be calculated as the

23 sum of the capacitance of the individual components. This is represented by the equation

퐶푒푞 = 퐶1 + 퐶2 + ... + 퐶푛. (2.6)

For capacitors in series, the total capacitance can be calculated as the multiplicative inverse of the sum of the reciprocals of individual resistors and represented by the formula 1 1 1 1 = + + ... + . (2.7) 퐶푒푞 퐶1 퐶2 퐶푛

Diode

Figure 2-3: The symbol used to represent a diode in circuit diagrams. The positive terminal is to the left, and the negative terminal is on the right.

A diode is a unidirectional conductor that passes current from a positive to negative terminal, and restricts current flow in the reverse direction. A typical diode utilizes a p-n junction material to generate a forward direction with zero resistance, and a backward direction of infinite resistance. A diode has two response modes known as reverse-bias and forward-bias. A diode that is reverse-biased will act as an insulator and will ideally prohibit current from being passed, so long as its voltage limit is not exceeded. Conversely, a diode that is operating with a forward-bias will become a conductor, and current can pass backwards through the diode. Diodes also possess a property known as breakdown voltage, which flips a diode’s bias when reached. When a diode is exposed to its breakdown voltage in the direction opposite the flow of current, the formerly infinite resistance drops to low resistance, andcur- rent backflows. This property is exploited to direct current in anomalous situations such as overvoltage. When an overvoltage situation occurs, a diode will switch from being negative-biased to being positively-biased, and will direct current away from sensitive components. Additionally, diodes have a characteristic voltage drop in the

24 direction of current flow, which is described in its commercial datasheet. This canbe used to help shape a voltage in signal processing.

Gain

In analog amplification systems like the SXM, gain refers to the ratio of outputto input signal. Voltage gain will be primarily discussed henceforth, as this is what occurs in the SXM amplification chain, although power, amplitude, and current are all other methods of measuring gain.

2.1.2 Operational Amplifiers

An Operational Amplifier, or op-amp is a high-gain voltage amplifier that takesa differential input and produces a single output. It is directly coupled, meaning that it relies on direct current transmission, rather than through inductive or capacitive coupling [2]. In a circuit diagram, an op-amp has five terminals, which are labeled in Figure 2-4.

Figure 2-4: A generic op-amp. (1) Inverting input, (2) Non-inverting input, (3) Positive power supply, (4) Negative power supply, (5) Output.

Additionally, an ideal op-amp has the following characteristics [2]:

∙ No output impedance

∙ No noise contribution to the output signal

25 ∙ No DC offset in the output signal

∙ Infinite bandwidth

∙ Infinite input impedance

∙ Infinite open-loop voltage gain

Open-loop gain is entirely dependent on the input. Consider Figure 2-5 in which an op-amp is placed in the open-loop configuration. For any non-zero voltage input, the open-loop gain drives the op-amp output into saturation. When the op-amp is saturated, the output voltage no longer increases. When the voltage input to the op-amp is zero, the output from the op-amp is also zero. An op-amp in the open-loop configuration is liable to latch-up, where the op-amp experiences a short circuit and ceases to work. Op-amp saturation is not always reversible, and can permanently disrupt current flow through the circuit.

Figure 2-5: A generic op-amp with open-loop gain.

In order to guard against voltage output saturation, an op-amp can be configured for closed-loop gain, as shown in Figure 2-6. Closed-loop gain relies on the output signal feeding back into the input in order to shape desired input. Op-amps that amplify through the use of closed-loop gain are less susceptible to voltage saturation through amplification. However, it should be noted that saturation can still occur through overvoltage from the input.

26 Figure 2-6: A generic op-amp with closed-loop gain.

2.1.3 Signal Amplification

The SXM uses a signal amplification chain to shape and condition x-ray flux signal for analog-to-digital conversion. Two different input configurations will be discussed in this section, and select common amplification circuits will be explained.

Inverting amplifiers take a positive DC voltage at the input and produce alarger negative voltage at the output. In AC amplification, the output is exactly 180 ∘) out of phase with the input. Non-inverting amplifiers take an AC input and preserve its phase in the amplified output. A positive voltage DC input will yield a positive voltage output.

The first common amplification circuit is a differentiator, shown in Figure 2-7.A differentiator is created using an inverting amplifier with a capacitor in the inputline, and a resistor in the negative feedback loop, which can be considered a rudimentary high-pass filter. This causes the output from the op-amp to be proportional tothe time derivative of the input, which is where the circuit owes its name. The differentiator has a few characteristic limitations. For instance, a differentiator is susceptible to circuit noise which may be amplified in the output. A differentiator is also susceptible to high-frequency noise, which can cause instability [2].

Similar to the differentiator, an integrator is used to integrate and invert an input signal. The output voltage is the time-dependent integral of the input voltage [2]. In

27 Figure 2-7: An example differentiator circuit. this configuration, a resistor is included on the input line, and a capacitor isplaced in the negative feedback loop, which creates a low-pass filter, as shown in Figure 2-8.

Figure 2-8: An example integrator circuit.

In its simplest configuration, an integrator circuit requires periodic discharge of the capacitor, which can become saturated with charge. When this occurs, the output voltage can drift beyond the optimal range of the op-amp. One way to mitigate this

28 challenge is to include a resistor in the feedback loop that functions as a discharge path for the loop capacitor (Figure 2-9).

Figure 2-9: An integrator circuit with an additional resistor added to the feedback loop provides a discharge path for the capacitor.

The last configuration worth mentioning is the Schmitt Trigger, which shapes an input signal into a square wave. An example Schmitt Trigger is provided in Figure 2-10. This configuration can be used to shape a signal at a set voltage, so that itcan achieve a more lossless input into an analog-to-digital converter. A Schmitt Trigger is a modified integrator with positive feedback. A voltage divider is used tosetthe positive feedback, and looped back to the non-inverting input. When a prescribed threshold voltage is exceeded, the input voltage triggers and changes the state of the output voltage. This configuration is vulnerable to hysteresis effects, where the input voltage is above the threshold voltage.

2.1.4 Analog-to-Digital Signal Conversion

Analog-to-digital conversion is the process through which an analog signal is trans- lated into a series of digital values using an analog-to-digital converter (ADC). In the SXM, an input x-ray signal is amplified and shaped before being converted and digitized for data processing. The digital output from the ADC is proportional to the

29 Figure 2-10: An example Schmitt Trigger. analog input signal, and is limited by quantization speed and accuracy concerns.

2.1.5 Thermal Impact on Circuitry

Temperature concerns must be accounted for when creating and operating complex electrical systems. Amplification circuits often have a small window of acceptable input voltages, and signals must remain within specified bounds in order to be amplified and ultimately converted by an ADC. Furthermore, unwanted over- or under-voltage can cause temporary or even irreversible damage to sensitive electrical systems. While voltage itself is not thermally dependent, individual circuit elements are dependent. For instance, an increase in temperature can affect power dissipation in resistors. This can cause permanent damage to resistors by burning or melting the resistor. In capacitors, temperature can alter how charge moves within a dielectric material, increasing or decreasing the amount of charge required to saturate the component. Additionally, resistivity in the wiring connecting circuit elements scales positively with temperature, which can cause unintended voltages within the circuit.

30 Temperature concerns are considered in the design process of space hardware. For Class D missions, NASA recommends that only Level 1, Qualified Manufacturer List Class V (QMLV) legacy hardware is used in instrumentation. Circuitry tested to this level is rated for interplanetary spaceflight, where extreme radiation and thermal conditions are experienced [10].

2.2 SXM Overview

The SXM component of the REXIS instrument suite is a subassembly located on the OSIRIS-REx bus such that it will face the sun during windows of operation that REXIS is pointed at Bennu. The electrical elements of the SXM are attached to the REXIS Main Electronics Board (MEB) by a coax tether. The SXM mechanically adheres to the spacecraft bus using an aluminum mounting bracket. The external elements of the SXM consist of an Amptek XR-100SSD silicon drift diode (SSD) detector connected to a pre-amplification circuit (henceforth referred to as the preamp) located on a mounted printed circuit board (PCB).

When a solar x-ray hits the SSD detector, an analog signal is passed through the preamp, where it is conditioned and sent to the MEB. At the MEB, the analog signal passes through an ADC, which outputs a digital response. This digital response is processed further by the MEB into x-ray energy event histograms sorted by energy level. Event energy data is kept in Analog-to-Digital Units, which can be converted to units of Electronvolt (eV). A conversion from ADU to eV is calculated using the formula 푘푒푉 = 0.0219 * 퐴퐷푈, (2.8) for the REXIS SXM.

Solar x-rays and their energies are then used to calculate the influx and energy of primary solar x-rays onto Bennu. A knowledge of primary x-ray energies is required to calibrate the secondary x-ray fluorescence capture by the REXIS detector.

31 2.3 SXM Data Pipeline

The SXM Data Pipeline takes a converted signal from the SXM ADC and processes it into data packets that are transmitted to the ground.

2.3.1 Instrument Response Modeling

The SXM underwent a series of ground and in-flight validations between 2013 and 2019. This section will focus on the instrument response modeling that was used to verify early in-flight observations. The SXM Data Pipeline included a model ofideal SXM response, which at its core took a sample time-series of x-ray detections and produced energy histograms. These energy histograms could then be fitted to a known solar abundance model, which would match an input signal to x-ray characteristics of elements in the Sun’s photosphere, and subsequently constrain solar temperature at the time of x-ray emission. While this function fell beyond the original scope of the SXM’s purpose, it provided yet another way to produce instrument science.

2.3.2 Chianti Atomic Database

The Chianti Atomic Database was used to create an instrument response model across all temperatures and energies observable by the SXM. The Chianti Database is an atomic spectra database built and maintained by a global consortium of atomic scientists [8]. Chianti and its associated python package, ChiantiPy, allow a user to generate model spectra of astrophysical bodies. For the purposes of the SXM, Chi- anti provided a known database against which sample SXM histograms could be matched. Both coronal and photospheric abundance models were generated at the temperatures and energies observable by the SXM, and ideal instrument response was cross-referenced against early in-flight calibration data that was taken prior to the REXIS instrument’s primary observation window. The intention of this cross- reference was to build reasonable confidence in the instrument response model such that temperatures and spectra abundances could be derived from data collected during observation.

32 Chapter 3

SXM Design and Operation

This chapter describes the design process and flight operations of the REXIS Solar X-ray Monitor (SXM). The first section will focus on the design constraints ofthe instrument. REXIS is a Risk Class D mission, which means it is a low budget instrument, and is designed to use legacy, off-the-shelf components [11],[12]. This section also describes the science mission requirements for the SXM, as well as design requirements stipulated by the OSIRIS-REx team. The design section will primarily detail the development of the SXM signal amplification chain, which is at the center of the Root Cause investigation found in Chapter 4.

The next section of this chapter will describe the testing battery used to characterize the SXM on the ground and in flight. The SXM’s pre-flight ground testing regimen will include testing data relevant to the SXM root cause analysis, and include rationale for why some tests were foregone. Results of SXM flight testing will be presented, and nominal x-ray count data will be shown.

The last section of this chapter summarizes SXM flight operations. A timeline of operations is included to understand where flight testing occurred relative to science observations. Flight operations are separated into three distinct phases, which corre- late to OSIRIS-REx mission phases. Early flight operations are described, followed by operations during Orbital B and Orbital R, the SXM’s two science operation phases.

33 3.1 SXM Design Background

The SXM was first designed as part of the 16.83 undergraduate capstone classin the MIT Department of Aeronautics and Astronautics in 2011. This first design became the foundation upon which the SXM flight model was developed. The REXIS instrument was designed to use heritage spaceflight technology to reduce the design timeline. The SXM detector is an Amptek XR-100SDD, which is an updated model of detectors flown on previous x-ray instruments. The XR-100SDD is an updated version of the XR-100CR, and the former uses a silicon drift diode, while the latter uses a PIN photodiode [1]. Both models a beryllium window above an evacuated chamber in which the detector is housed. Amptek XR-100CR detectors were used in the Solar X-ray Spectrometer aboard GSAT-2, a space-based Indian solar observatory [5]. A similar Russian space observatory used the XR-100CR in the Solar Photometer in X-rays (SphinX) instrument [15]. Both of these previous instruments demonstrated that the Amptek XR-100 class detector could be reasonably be used to for x-ray solar observation, despite the XR-100SDD never having flown prior to REXIS.

The XR-100SDD detector was also included in early designs of the Neutron star Interior Composition ExploreR (NICER) instrument. NICER was developed by the MIT Kavli Institute (MKI), and the engineering teams worked closely together in the development processes. Both Professor Richard Binzel and Dr. Rebecca Masterson, who represent two-thirds of REXIS leadership, are affiliated with the Kavli Institute. Additionally, the Kavli Institute is located in the same building as the REXIS team, meaning collaboration was as easy as going upstairs. Additionally, the Goddard Spaceflight Center serves as the managing center for both REXIS and NICER. This closeness of personnel was reflected in the design of the REXIS SXM.

The NICER instrument is mounted aboard the International Space Station, where its main spectrometer observes neutron stars in the 0.2 to 12 keV range [4]. The REXIS SXM shares both structural and electronic heritage with the NICER instrument. An early design of NICER implemented 56 XR-100SDD detectors, the same detector used by the REXIS SXM. The NICER team later changed their design to

34 use an Amptek CMOS detector, which benefits from higher temporal resolution. While the NICER instrument and the REXIS SXM’s designs diverged during the design phase, the SXM was heavily influenced by this early NICER design. The design of the SXM preamp circuit and SXM Electronics Board resemble the NICER pream- plifier board and surrounding electronics housing respectively. These similarities are the legacy of John Doty, an engineer affiliated with MIT who created the SXM timing circuitry, signal pulse shaping, and threshold trigger. A complete documentation of SXM circuit diagrams can be found in Appendix A.

3.1.1 Mission Requirements

REXIS SXM requirements fall under the REXIS instrument’s main requirements, which in turn are derived from OSIRIS-REx requirements for the instrument. The REXIS requirements documentation flow was described extensively in Mike Jones’s Master’s thesis [6]. The information flow diagram for REXIS is shown in Figure 3-1

Figure 3-1: The REXIS Requirements documentation flow from Jones, 2015 [6].

The SXM’s energy band of interest is from 0.6 keV to 6 keV. Quantum efficiency for the SXM is also outlined in the REX-74 requirement. Quantum efficiency is the

35 ratio of photon events that are successfully converted to electrons by the detector, and is a metric used to evaluate the performance of an instrument at different detection energies (shown in Table 3.1).

Quantum Efficiency Energy Range (keV) >0.01 0.62 - 0.7 >0.03 0.7 - 0.8 >0.09 0.8 - 1.2 >0.65 1.6 - 2.8 >0.85 2.8 - 4.1 >0.9 6.0 - 7.0

Table 3.1: Quantum Efficiency Requirements for the SXM Detector.

The REXIS SXM Requirements are derived from the different levels of REXIS requirements. SXM operational and environmental requirements are found in the Level 4 documentation. Level 3 documentation describes the requirements for detector functionality. The Level 2 requirement REX-7 is the highest-level requirement pertaining to the SXM. REX-7 requires that the SXM "shall measure solar coronal temperature to within 0.1 MK every 50 sec while observing Bennu in Phase 5B as- suming a single temperature model." A complete overview of Level 3 and Level 4 requirements can be seen in Tables 3.2 and 3.3.

ID No. Title Description REX-225 Integration The SXM shall integrate counts for 32 Time seconds (nominally) to form a spectrum. REX-73 Spectral Resolu- The SXM shall have a spectral resolution tion (FWHM) that is less than 200 eV from 0.6 to 6 keV. REX-74 Quantum Effi- The SXM shall detect x-ray events from ciency 0.6 to 6.0 keV with quantum efficiencies as given in Table 3.1. REX-75 Field of View The SXM shall have a full width zero intensity (FWZI) FOV of no greater than 60 deg full cone and a full width full intensity (FWFI) FOV of no less than 10 deg full cone.

Table 3.2: SXM Level 3 Requirements.

36 ID No. Title Description REX-228 SDD Survival The temperature of the SDD shall al- Temperature ways be greater than -65∘C and less than 150∘C. REX-229 SDD Operating The temperature of the SDD shall be Temperature less than -30∘Cand greater than -70∘C. REX-76 Preamp Survival The temperature of the SXM Preamp Temperature shall be greater than -55∘C and less than 85∘C. REX-77 Preamp Operat- The temperature of the SXM preamp ing Temperature shall be greater than -40∘C and less than 85∘C while operating. REX-78 SXM Health The SXM shall survive and remain operational through the end of Phase 8. REX-79 SXM Opera- The SXM shall be capable of operating tional Time 24 hours per day

Table 3.3: SXM Level 4 Requirements.

3.1.2 Overview of SXM Signal Amplification Chain

The SXM amplification chain is responsible for priming a signal from the SDDde- tector before it is converted by the Analog-to-Digital Converter (ADC). The amplification chain is housed on the SXM Main Electronics Board (MEB), which is located within the REXIS instrument on the spacecraft. The SXM detector and preamp circuit are housed in the SXM backpack, which is bolted to the outside of the spacecraft, and is connected to the MEB by a coaxial cable. The SXM detector housing is shown in Figure 3-2. The SXM ADC requires a positive voltage signal pulse to be passed to it in order to register a detection count. When an x-ray strikes the detector, an analog signal pulse is created. The raw signal biased at 3.3 V, sent through the preamp, and then sent across the coax cable to the MEB. When the signal reaches the MEB, it is passed through three opamps, which amplify the signal. Then the voltage signal is divided, where one signal passes through an integrator circuit and the other signal through a differentiator circuit. The output from the integrator circuit is labeled outu, and the output from the differentiator circuit is labeled outb. The amplification chain schematic diagram is shown in Figure 3-3. Additional SXM electronics schematics

37 Figure 3-2: SXM detector and preamp housing. The SXM detector is located below the collimator.

can be found in Appendix A. The signals are then sent through a low pass filter to eliminate high frequency noise artifacts added to the signal when it passed through the preamp circuit. The outu signal is then sent to the final section of the amplification circuit, where 3Vof bias are subtracted, leaving the signal with a residual 0.3 V bias. This bias is required to keep the outu signal positive because the ADC used in the SXM electronics chain is not rated for negative voltage inputs. Next, Signal outu is sent to the ADC to be measured, while signal outb is sent to a zero cross monitor, which provides the timing for the ADC to sample new signal, now named outu1. In order to trigger an ADC detection, the SXM relies on a trigger circuit that uses a series of comparators to compare outb to a reference voltage. The trigger circuit is shown in Figure 3-4. This trigger includes a command to manually set the threshold Voltage Lower Limit of Detection (VLLD). The VLLD is set above the outb bias voltage as well as the noise floor to prevent the SXM from accidentally triggering due to random noise in the electronics. The relationship of outb to VLLD is given as:

퐿퐿퐷 = outb − 푉 퐿퐿퐷, (3.1)

38 39

Figure 3-3: Schematic of SXM Amplification Chain. Outputs outb and outu are seen on the far right. Figure 3-4: SXM Trigger Circuit Schematic. where LLD is the Lower Limit of Detection. A threshold setting anomaly was discovered early in flight, where the threshold would fluctuate. This was resolved by sending

40 three threshold setting commands to the instrument. The first two commands were to set the threshold to an arbitrarily high value, and the third command was to set the threshold to the intended value. This workaround was only used once, but resolved noticeable threshold drift for the remainder of flight. The second threshold circuit is used to determine the zero crossing of outb. When outu1 is at it’s peak, outb will have a zero crossing, and the ADC is triggered to begin recording. Figure 3-5 shows an example of all signal shapes.

Figure 3-5: SXM signals at various points throughout the amplification chain.

41 3.2 Instrument Testing

As part of the instrument design process, the REXIS SXM was subject to numer- ous functionality tests on the ground. Testing was limited by time and financial constraints, but the testing framework was rigorous and proved the SXM ready for flight. The subsection on ground testing will focus on testing that aided incharac- terizing the SXM low count rate anomaly discussed in Chapter 4. A more thorough description of SXM ground testing can be found in Kevin Stout’s thesis [14]. The SXM also underwent a series of flight tests between launch in 2016 and Orbital B, the first data collection phase, in July of 2019. Flight testing was primarily used to characterize the REXIS main spectrometer, whose CCD array required in-flight calibration, although the SXM was tested as well [7].

3.2.1 Ground Testing

The SXM was put through a battery of ground tests to ensure the instrument was ready for flight testing. The testing procedure followed NASA requirements forRisk Class D missions [11]. The focus of this subsection will be on SXM thermal tests, which provided a background for the root cause analysis outlined in Chapter 4. The SXM was subject to thermal testing using thermal vacuum chambers built in the MIT Space Systems Laboratory and at MIT Lincoln Laboratory.

SXM Oven Test

The SXM MEB underwent an oven test at Lincoln Laboratory in November of 2015. The complete SXM flight assembly, including the preamp and SDD detector, were placed in a thermal chamber. The MEB remained connected to the SXM assembly, but outside the chamber. The MEB was held at a temperature of approximately 20∘C. The temperature of the thermal chamber was then fluctuated between -40∘C and 60∘C with a ground calibration iron source to measure instrument performance as a function of temperature. This was a more drastic temperature fluctuation than was expected in flight, and was used to identify thermal vulnerabilities in theSXM.

42 An example histogram from the ground calibration source is shown in Figure 3-6.

Figure 3-6: SXM Histogram of Ground Calibration Source. A strong iron line can be seen at around 200 ADU.

The preamp and SDD detector remained insensitive to temperature fluctuations over the test range. Additionally, it was discovered that both low and high energy artifacts set in at approximately 53∘C. The results of this test are provided in Figure 3-7.

MEB Thermal Characterization

The SXM MEB was included in a similar thermal test. The MEB was placed in the thermal test chamber, where its temperature was then cycled between -40∘C and 60∘C, while the SXM was exposed to the Fe-55 ground calibration source. Figure 3-8 shows temperature changes in the SXM during testing. At high temperatures, the SXM recorded lower source counts than at lower temperatures. Hysteresis effects were also seen in the MEB, and it was determined that

43 Figure 3-7: Results of SXM Oven Test, November 2015.

Figure 3-8: Temperature Fluctuations during the MEB Thermal Characterization Test.

temperature changes in the MEB can result in changes to the SXM’s low energy threshold. The results of this test are provided in Figure 3-9.

44 Figure 3-9: Ground Testing results of MEB susceptibility to temperature fluctuations.

3.3 Flight Operations

This section will describe the REXIS SXM during flight operations, from launch in September 2016 to planned shutdown in November 2019. The REXIS SXM operated over a period of approximately 3.5 years. The SXM was first powered on during L+14 days for a payload functions check. It was powered on at various times in flight during which it underwent calibration and additional functions checks. The SXM entered its first data collection phase in July, 2019 during Orbital B. Due to unanticipated low x-ray counts during Orbital B, it was powered on for an additional observation window in November, 2019 as part of the Orbital R mission phase.

3.3.1 Early Flight Operations

Early flight operations for the SXM were characterized by a series of functionality tests, which served as milestones towards the ultimate goal of data collection during the Orbital B mission phase. The first of these calibrations occurred during the L+14 days payload check. The SXM collected 3935 seconds of nominal x-ray data, and the instrument was determined to be working properly. The next notable evaluation of the SXM occurred during L+30, which took place in January, 2019. L+30 was the first time that Bennu was in the field of view ofthe REXIS main spectrometer, and was a critical functionality check for the instrument.

45 The L+30 mission phase was divided into two distinct flight patterns. The first had the REXIS main spectrometer pointing nadir at the asteroid, while the second had the main spectrometer pointing away from the asteroid. During the second phase of L+30, the SXM recorded a low x-ray count rate from the sun, which was because the instrument was not directly facing the sun, as it was during the first phase of L+30. A comparison of L+30 flight data are shown in Figure 3-10. This example of off-pointing low x-ray counts became an important comparison data set with which to compare Orbital B data.

3.3.2 Flight Operations during Orbital B

The SXM entered its primary data collection phase during Orbital B, which occurred in July, 2019. On 5 July, the SXM suffered a "bit flip" error, where each detection was saturated by an additional value of 34880. This was noticed when the daily histogram data was saturated at an extremely high count rate. The "bit flip" most likely occurred when the SXM was struck by a high energy cosmic ray, which shifted the reset value of the SXM from its minimum value to its maximum. This required a reset of the instrument from the ground, which reverted the SXM reset value to its designed minimum.

Once the "bit flip" had been resolved, the SXM remained operational for therest of Orbital B. During Orbital B, the SXM recorded an x-ray count rate two orders of magnitude lower than what was previously seen during the first part of Internal Calibration. An example event rate histogram from Orbital B is shown in Figure 3-11.

Low x-ray counts persisted for the remainder of Orbital B, and were subsequently the focus of an anomaly report made to the OSIRIS-REx team. These low x-ray counts were unexpected, and highlighted anomalous performance in the instrument, give the spacecraft’s heliocentric distance, and the solar state. While the Sun was recorded at a quiet A6.7 state, x-ray counts should have reflected a higher solar flux.

46 (a) Nadir Pointing REXIS Main Spectrometer

(b) Off-Point REXIS Main Spectrometer

Figure 3-10: SXM Event Rate Histograms during L+30

3.3.3 Flight Operations during Orbital R

The REXIS instrument team requested an additional observation due to lower than anticipated counts by the SXM and REXIS main spectrometer during Orbital B. The OSIRIS-REx mission operations team allowed the REXIS instrument to have an additional observation window during Orbital R, which took place during November

47 Figure 3-11: SXM Event Rate Histogram from Orbital B, 25 July 2019.

2019. It was hoped that when REXIS was powered on for Orbital R, the main spectrometer would detect higher flux counts from the asteroid, and the SXM would report x-ray counts at the expected rate. During Orbital R, the SXM recorded low x-ray counts similar to those seen in Orbital B. An example Orbital R event rate histogram is shown in Figure 3-12. As Orbital R progressed, the SXM event rate began to decline. This coincided with a change in temperature in the SXM MEB, which occurred on 18 November, 2019. The secondary count drop off occurred rapidly over the course of the day, and can be seen in Figure 4-4. The SXM recorded low counts for the remainder of Orbital R. An investigation of the cause of these low x-ray counts in described in Chapter 4.

48 Figure 3-12: SXM Event Rate Histogram from Orbital R, 13 November 2019.

49 50 Chapter 4

SXM Root Cause Analysis

This chapter presents a preliminary root cause analysis of the SXM low count rate anomaly that began on 3 July, 2019, at the beginning of the Orbital B observation window. A root cause was chosen to examine the failure of the SXM as an instrument. It consists of an investigation into all possible causes of failure, which is the fourth probable cause described in a fishbone diagram (shown in Figure 4-1).

Figure 4-1: Example Fishbone diagram used to outline a Root Cause Analysis. Each bone is used to categorize the type of cause.

Based on evidence collected during a preliminary investigation by the instrument team, the most likely cause of low x-ray counts in the SXM was hypothesized to be due to a change in temperature in the signal amplification change. This thesis

51 will focus on the subsequent investigation of the thermal vulnerability of electronic components in the SXM. A brief explanation will be given for why other bones on the fishbone diagram have been discounted as the causes of failure. In this chapter, an investigation report delivered to the OSIRIS-REx PI will be presented. A section will be devoted to how the anomaly was first identified, and the methods used to bound the problem. SXM response modeling to Orbital B data will be shown, and how it corresponds to deviations in the SXM’s long-term temperature. LTSpice simulations show that modeling capabilities are limited by vendor simulation code, and leave a path forward for further research. A preliminary conclusion is offered, and a recommendation for future investigation is provided. As apointof reference, the terms "count rate" and "event rate" will be used interchangeably, as the SXM histogram data are recorded as counts (or particles striking the diode detector) per energy level, recorded in 32 second bins.

4.1 SXM Low Count Rate Anomaly

The SXM received lower than expected counts during its two observation windows. This problem was first identified in Orbital B, and was subsequently observed inall of Orbital R as well. It was an ongoing impediment to solar science using the SXM, and its exact cause remains an open area of investigation.

4.1.1 Orbital B

The SXM low count rate anomaly was first discovered during Orbital B, which took place in July and August of 2019. The SXM showed a decreased count rate that was atypical for the spacecraft’s heliocentric distance. At this time, the spacecraft was located at a heliocentric distance of 1.3AU, and was showing a solar state of A6.7 as recorded by GOES15, a solar observatory located in Low Earth Orbit (LEO). An A6.7 solar state is relatively quiet from the sun, which at this time was near solar minimum, a period of low solar output. Orbital B data were two orders of magnitude lower when compared to signal data taken during Internal Calibration, during which

52 the spacecraft was at a comparable heliocentric distance.SXM data from Orbital R show a similar signal discrepancy, shown in Figure 4-2.

Figure 4-2: SXM count rate histogram from launch to Orbital R.

During Orbital B, the SXM also suffered an unrelated "bit flip" error, which caused each histogram bin to increase by a value of 34880. The bit flip was most likely caused by a strike from a stray high energy particle, which caused the 16-bit reset value to wrap around from 0 to 34880, the maximum value. This was first observed on 5 July, 2019, and resulted in a saturated event rate histogram. When this value was subtracted from these data, the corrected histogram showed values similar taken the previous day. A comparison of the saturated and corrected histogram is shown in Figure 4-3. The bit flip was corrected by manually resetting the histogram minimum value, which could be done from the ground. There were no issues with saturation in the SXM event rate for the remainder of Orbital B. The reset of the SXM offset did not impact the low count rate issue previously identified.

53 Figure 4-3: SXM Saturated Histogram (Right) and Corrected Histogram (Left)

4.1.2 Orbital R

Due to low counts during Orbital B, REXIS was allotted an additional 15 day observation window during November, 2019. On 18 November, 2019, SXM signal during Orbital R decreased beyond the low count rate seen in Orbital B, which can be seen in Figure 4-4. This decrease in signal is distinct from the previous six days observation in Orbital R, and demonstrates a departure from the previous low-count issue. This second decrease in signal persisted for the remaining 7 days of Orbital R. A notice was provided to the OSIRIS-REx PI following the first instance of a lower than anticipated count rate during Orbital B. A subsequent incident, surprise, anomaly report (ISA) was requested, which was the formal directive for a root cause analysis into the instrument anomaly.

4.2 Constraining the Problem

Once the low count-rate anomaly had been identified, it became necessary to provide boundaries on the investigation. The following section begins with an overview of the ISA report and provides a fishbone diagram of the five likely root causes, as well the rational behind selecting thermal variability in the SXM Main Electronics Board (MEB) amplification chain as the most likely root cause.

54 Figure 4-4: SXM count rate histogram on 18 November, 2019. The gap in the histogram is when the instrument was not recording data, and is unrelated to the low count rate anomaly in Orbital R.

4.2.1 ISA #10939

The OSIRIS-REx PI’s office opened a formal Incident, Surprise, Anomaly (ISA) investigation into the SXM low count rate. At the conclusion of Orbital B, this investigation was not time sensitive, as REXIS had completed its only observation phase, collected all possible data, and had been powered off according to OSIRIS-REx power mission design.

A fishbone diagram was created to illustrate the possible causes of a low instrument count rate in the SXM. The fishbone diagram included in the SXM low count rate ISA is shown in Figure 4-5.

Each potential cause of the SXM low count rate shown in the fishbone diagram will be explained briefly.

55 Figure 4-5: Fishbone diagram constructed for OSIRIS-REx ISA #10939

SXM SDD Detector was Occulted

The SXM SDD detector being occulted was a natural concern for the instrument team. The OSIRIS-REx team discovered that Bennu is an "activated asteroid," which is characterized by dust ejecta from the asteroid’s surface [3]. If particulate matter partially or completely occulted the SXM field of view, then the instrument would receive lower counts than predicted. However, it is unlikely that particulate blockage occurred, as the SDD detector is small, and the spacecraft took extreme care to avoid ejecta.

Another way that the SXM might have been physically occulted is if part of the spacecraft, for example foil used to insulate sensitive electronics, became dislodged and migrated to cover the detector. Parts of the spacecraft are lined with mylar, which acts as a thermal insulator. This too is unlikely, as the spacecraft’s guidance and control team would notice a change in spacecraft motion.

56 Internal Collimator Shifted

The Internal Ring Collimator is attached to the exterior of the preamp housing, and acts as a pinhole for solar x-ray flux. The collimator is attached to the preamp in such a way that if the collimator shifted, it would disconnect critical SXM wiring. This would appear as a total loss of signal in the instrument, rather than as reduced x-ray counts. It was determined that the SXM did not suffer a complete loss of signal after the SXM observed a solar flare. The timing of the flare detected by the SXM coincided with flare data observed by one of the GOES satellites (Figure 4-6). GOESisan Earth-orbiting satellite constellation that monitors solar phenomena and provides persistent solar observation.

Figure 4-6: Flare Coincidence between the SXM and GOES15.

Voltage Shift in SXM Driver Circuit

Another possibility considered was that the SXM driver circuit’s voltage had shifted. The driver circuit was directly linked to the Analog-to-Digital Converter (ADC) at

57 Figure 4-7: SXM longterm HV for its operational lifetime. the end of the amplification chain. A departure from the designed driver voltage would cause the ADC to convert less analog signal. SXM long-term High Voltage (HV) did not deviate by more than ± 1 V, as seen in Figure 4-7. Thus, a voltage shift in the driver circuit can be eliminated from the list of possible root causes for the low count anomaly.

Dark Current Increase

It is unlikely that dark current increased in the SXM during Orbital B. Ground testing indicated that dark current was not a significant concern for the SXM when it was cooled to operational temperature. Dark current was found to cause more frequent resets when the SDD detector was warm [6].

Temperature Shift in the Amplifier Electronics Chain

The most likely possibility remaining unaccounted for in the fishbone diagram was a temperature change in the signal amplification chain located on the Main Elec- tronics Board (MEB). The SXM showed sensitivity to temperature changes in the MEB during ground testing, which included suppressing low energy signal at higher temperatures. Figure X shows an SXM oven test that illustrates ground test thermal susceptibility.

58 Additionally, the second decrease in SXM signal during Orbital R coincided with a thermal change on the spacecraft. Inertial Measurement Unit 1 (IMU1) was switched off, and IMU2 was powered on. The inertial measurement units provide the OSIRIS- REx navigation team with the exact position of the spacecraft, and where it is located with respect to Bennu. When the IMU changeover occurred, the SXM entered a new phase space (shown in Figure X), where the Thermo-Electric Cooler (TEC) temperature decreased, and the temperature doubled in the Detector Electronics (DE), where the REXIS main spectrometer’s video board is housed. The SXM backpack electronics were not effected by this thermal change.

Figure 4-8: SXM Temperature Phase Space.

This dramatic shift in SXM temperature phase space indicated that low count rate was related to a change in MEB temperature. The SXM operated in a new phase space for both Orbital B and Orbital R when compared to previous data, which coincided with lower signal counts. This sensitivity was reported in the ISA #10939 briefing, and it was determined that the SXM was still functional above 3keV.The low count anomaly presented no threat to any other spacecraft system, and it was recommended that additional work focus on further isolating the root cause.

59 4.2.2 Modeling SXM Instrument Response

Once it had been established that SXM signal was reduced below its expected value, rather than totally lost, efforts were made to recover the signal. If it was possible to recover the signal, SXM data could still be used to measure solar temperature. Solar temperature measurements can be used to calculate solar output, which in turn makes it an essential step in characterizing the Sun’s input to Bennu’s surface.

The most prominent of these attempts involved rebinning SXM data. Since the SXM was reporting a 100x loss in signal, it was thought that signal could be amplified by rebinning 100 histograms together. The original SXM histograms showed32 seconds of data. Rebinned histograms combined 3200 seconds of data into a single histogram. Rebinning histogram data required writing additional code to interface with the existing Data Pipeline. Data were separated by collection phase, with Or- bital B consisting of one dataset, and Orbital R divided into two, differentiated by which IMU was employed.

Data were rebinned using a sliding bin technique, which used a 3200 second window of data and took averages of the energies of the individual histograms and produced a stacked histogram. Sliding binning was employed to prevent individual high- count histograms from skewing binned data. A limitation to rebinning was that it raised the high energy noise as well as improved signal, which is shown in Figure 4-9. Rebinning also amplified instrument artifact, which binned at an disproportionate rate when compared signal.

Rebinning was ultimately unsuccessful at extracting SXM signal from the low count rate data. Rebinning recovered artifacts back to levels seen in the Internal Calibration, but failed to recover signal to the same levels. Signal could not be recovered to the levels of previous quiet sun data, and further rebinning attempts were abandoned, and efforts were focused on identifying thermally susceptible electronics.

60 Figure 4-9: SXM Histogram Rebinning. The boxed area surrounds the SXM’s main signal peaks. The peaks at the outer edges of the figure are instrument artifacts.

4.3 LTSpice Simulations of Amplification Chain

The SXM amplification chain proved to be the most promising path towards isolating a root cause of the low count anomaly. As was previously explained in Section 4.2.1, the SXM was susceptible to temperature changes in the MEB. This temperature vulnerability was not seen in the ground spare unit, and MIT’s closure due to COVID- 19 prevented any further ground testing. Computer simulation of the SXM electronics using LTSpice was chosen as an alternative to physical testing. LTSpice can simulate circuits across multiple temperatures and signal inputs, making it an excellent choice to investigate thermal vulnerability. LTSpice is a free software distributed by Analog Devices, which allows a user to build and test circuits. LTSPice allows a user to upload proprietary component models, which are produced by electronics hardware companies. These proprietary models incorporate existing LTSpice modeling code and data from a component’s spec sheet. The opamps used in the SXM amplification chain are produced by MAXIM In-

61 tegrated, an electrical components company that produces analog and mixed-signal integrated circuits. MAXIM Integrated offers LTSpice models for their components on their website, which are free to download and developed by their engineering staff. LTSpice has two simulation modes: a netlist, and a schematic. A netlist utilizes Spice syntax and works similar to common coding languages. Components and their values are added to a netlist, and connections to other components are written in LTSpice’s netlist syntax. LTSpice schematics are drawn or imported by the user, and have a more robust visual interface. LTSpice schematics are nearly identical to KiCAD and other schematic design software. Both a netlist and schematic can be used to simulate the same circuit.

4.3.1 Thermal Variability in Components

The SXM had an existing netlist from previous simulation, which required minor changes due to software updates. The simulation procedure involved running the circuit for 10ms, with a global electronics temperature range from 0∘C to 30∘C, run at steps of 5∘C. A voltage pulse was used as the input signal, which represented a single detection by the SXM. However, the simulation would not run when given the stepwise temperature procedure. LTSPice refused to run at the upper and lower bounds of the simulation. The range of testing was modified to run between∘ 20 C and 30∘C, within the range of temperatures seen by the MEB during Orbital B and Orbital R. Again, temperatures at the extremes of the range were unable to be simulated by LTSpice. The simulation worked at a temperature of 27∘C, but the total time to simulate the circuit increased as the temperature moved closer to 20∘C and 30∘C. The increased simulation time was considered to be a result of high-frequency noise, which was believed to indicate that the amplification chain had components that were highly vulnerable to noise, near operational temperatures. This could not be well established with the netlist, as the netlist could not simulate flight temperatures seen in Orbital B, Orbital R, or from any previous flight data with which to compare. The validity of the existing netlist was called into question, and it was decided

62 to try to create a schematic of the amplification chain from scratch, to avoid any preexisting errors that could have propagated from the updating of the old netlist.

The amplification chain was recreated in LTSpice using the electronics schematic for the SXM. The MAX4416ESA opamp model was placed in the electronics chain to provide an accurate simulation of signal amplification. The LTSpice schematic of the amplification chain is provided in Figure 4-10.

The simulation was conducted with the same reduced range as the netlist, and again faced the same challenges as the simulation run from the netlist. To eliminate the possibility that the simulations were failing due to computing limitations, the circuit was broken up into five distinct sections, and each contained only one opamp.

Each subcircuit was tested within the same 10∘C temperature range. The simulation crashed at same temperatures seen in prior simulations. Consistent simulation failures at the same temperature across multiple configurations was hypothesized to be the result of faulty opamp code. A simulated test circuit was constructed, where the MAX4416ESA opamp was given a generic input and output within its range of operation. The test circuit was run with the same 10∘C temperature range, and the range at which the simulation ran properly was constrained to between 22∘C and 29∘C. This pointed to a limitation in the opamp Spice model, which was confirmed through a series of emails with MAXIM Integrated. The thermal constraint is a known limitation from the manufacturer, which was not published with the Spice model. This was unknown to the REXIS team until April 2020. Additionally, efforts to freeze the opamp model at a local temperature, and run the LTSpice simulation at a different global temperature were unsuccessful.

This revelation made further thermal investigation with LTSpice a fruitless en- deavor. The temperatures seen by the MEB during Orbital B and Orbital R were out of range of the model of the opamp used in the amplification chain. While these results are inconclusive, there is further work that can be done towards isolating the root cause of the low count rate anomaly.

63 64

Figure 4-10: The SXM Signal Amplification Chain. 4.4 Root Cause Next Steps

The SXM low count rate anomaly remains an open area of investigation. The SXM is a model instrument for other Class D missions, and instrumentation and programmatic lessons learned will allow other instruments to learn and improve from the SXM. Despite the limitations of circuit simulation, there are avenues to continue the root cause analysis. This section will describe two areas of future work, a continued root cause investigation, and a CAST analysis, which will together serve as the crux of my Master’s thesis.

4.4.1 Identification of Vulnerable Components

There is still work to be done on a root cause investigation into the low count anomaly. The hypothesis that there are temperature-sensitive components in the SXM amplification chains has not yet been proven wrong. Identifying vulnerable components is important for the NICER team, from which the SXM amplification chain schematic was derived. There is a possibility that NICER is operating with the same vulnerability in their detector chain, and a known vulnerability could be planned for, or worked around by the instrument team.

4.4.2 CAST Analysis

Another approach to isolating the cause of the low count rate anomaly is through a Causal Analysis based on System Theory (CAST) investigation. CAST is used to examine the programmatic and control factors that may have influenced an event. While this will not provide further information towards which components in the SXM amplification chain are thermally vulnerable, it offers a way to document lessons learned at a programmatic level. This includes decisions to prioritize some ground tests over others, and decisions made in instrument development. CAST also documents suc- cessful control measures that were implemented throughout the project that guarded against other accidents. The goal of this future CAST investigation is to produce a definitive list of lessons that can be used by future instrument teams in their design

65 and testing process.

66 Bibliography

[1] Amptek. Manual for the Silicon Drift Diode Detector Element.

[2] Bruce Carter and Thomas R. Brown. Handbook of Operational Amplifiers Ap- plications. Texas Instruments.

[3] H. C. Connolly, E. R. Jawin, R. L. Ballouz, K. J. Walsh, T. J. McCoy, D. N. Dellagiustina, K. Burke, E. B. Biehaus, B. Rizk, C. D’Aubigny, V. E. Hamilton, W. F. Bottke, J. P. Dworkin, M. Delbo, S. Tachibana, H. Yurimoto, and Orisis- Rex Team. OSIRIS-REx Sample Science and the Geology of Active Asteroid Bennu. In 82nd Annual Meeting of The Meteoritical Society, volume 82, page 6209, July 2019.

[4] Keith Gendreau, Zaven Arzoumanian, and Takashi Okajima. The neutron star interior composition explorer (nicer): An explorer mission of opportunity for soft x-ray timing spectroscopy. Proceedings of SPIE - The International Society for Optical Engineering, 8443:13, 09 2012.

[5] Rajmal Jain, Hemant Dave, AB Shah, N. Vadher, Vishal Shah, G. Ubale, K. Ma- nian, Chirag Solanki, K. Shah, Sumit Kumar, S. Kayasth, V. Patel, Jayshree Trivedi, and M. Deshpande. Solar x-ray spectrometer (soxs) mission on board gsat2 indian spacecraft: The low-energy payload. Solar Physics, 227:89–122, 03 2005.

[6] Michael Jones. The engineering design of the rexis solar x-ray monitor and risk management considerations for resource constrained payload development. Master’s thesis, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02219, May 2015.

[7] Madeline Lambert. A root cause analysis of rexis detection efficiency loss during phase e operations. Master’s thesis, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02219, May 2020.

[8] E. Landi, P. R. Young, K. P. Dere, G. Del Zanna, and H. E. Mason. CHI- ANTI—AN ATOMIC DATABASE FOR EMISSION LINES. XIII. SOFT x- RAY IMPROVEMENTS AND OTHER CHANGES. The Astrophysical Journal, 763(2):86, jan 2013.

67 [9] D. S. Lauretta, A. E. Bartels, M. A. Barucci, E. B. Bierhaus, R. P. Binzel, W. F. Bottke, H. Campins, S. R. Chesley, B. C. Clark, B. E. Clark, E. A. Cloutis, H. C. Connolly, M. K. Crombie, M. Delbó, J. P. Dworkin, J. P. Emery, D. P. Glavin, V. E. Hamilton, C. W. Hergenrother, C. L. Johnson, L. P. Keller, P. Michel, M. C. Nolan, S. A. Sandford, D. J. Scheeres, A. A. Simon, B. M. Sutter, D. Vokrouhlický, and K. J. Walsh. The osiris-rex target asteroid (101955) bennu: Constraints on its physical, geological, and dynamical nature from astronomical observations. Meteoritics & Planetary Science, 50(4):834–849, 2015.

[10] NASA. EEE-INST-002: Instructions for EEE Parts Selection, Screening, Qual- ification, and Derating.

[11] NASA. NPR 8705.4.

[12] NASA Goddard Spaceflight Center. Code 300/Safety and Mission Assurance Directorate. Goddard Procedural Requirement 7120.4: Risk Management.

[13] Andrew Poppe, David James, Brian Jacobsmeyer, and Mihály Horányi. First results from the Venetia Burney Student Dust Counter on the New Horizons mission. , 37(11):L11101, June 2010.

[14] Kevin Stout. Design operations of thermal paths in spacecraft systems. Mas- ter’s thesis, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02219, May 2015.

[15] Janusz Sylwester, S. Kuzin, Yury Kotov, František Fárník, and Fabio Reale. Sphinx: A fast solar photometer in x-rays. Journal of Astrophysics and Astron- omy, 29:339–343, 06 2008.

68 Appendix A

SXM Circuit Schematics

The following Appendix contains the circuit diagrams of all sections of the REXIS SXM. This Appendix also serves as a means through which to document the design of the SXM.

69 REXIS MAIN ELECTRONICS BOARD ENGINEERING MODEL SCHEMATICS

PAGE 1- TABLE OF CONTENTS PAGE 2- TI 8:1 ANALOG TO DIGITAL CONVERTER PAGE 3- SPACECRAFT COMM INTERFACE PAGE 4- EXTERNAL CONNECTORS - SXM AND PRTS PAGE 5- FRANGIBOLT RADIATION COVER RELEASE MECHANISM ACTUATION PAGE 6- GROUNDING PAGE 7- HOUSEKEEPING VOLTAGE GENERATION PAGE 8- AEROFLEX 64MBIT NOR FLASH PAGE 9- PRIMARY POWER PAGE 10- POWER 1.0V PAGE 11- POWER 2.5V PAGE 12- POWER 3.3V AND -5V POWER PAGE 13- 3D-PLUS 1GBIT DDR SDRAM PAGE 14- SWITCHES PAGE 15- SOLAR X-RAY MONITOR DAC & ADC PAGE 16- SOLAR X-RAY MONITOR AMPLITUDE PAGE 17- SOLAR X-RAY MONITOR COCKCROFT WALTON HIGH VOLTAGE GENERATOR PAGE 18- SOLAR X-RAY MONITOR SHAPING AND AMPLIFICATION PAGE 19- SOLAR X-RAY MONITOR TEC DRIVER PAGE 20- SOLAR X-RAY MONITOR TEC TEMPERATURE INTERFACE PAGE 21- SOLAR X-RAY MONITOR THRESHOLD CONTROL PAGE 22- SOLAR X-RAY MONITOR TRIGGER AND TIMING PAGE 23- PRT TEMPERATURE MEASUREMENT INTERFACEPRT INTERFACE PAGE 24- VIRTEX-5 BANKS 0-4, CONFIGURATION ADDRESS, OSCILLATOR PAGE 25- VIRTEX-5 BANKS 11,12,13 AND 15 PAGE 26- VIRTEX-5 BANKS 17,18 AND 19 DETECTOR ELECTRONICS CAMERA LINK INTERFACE PAGE 27- VIRTEX-5 BANKS 20 AND 21 DDR SDRAM DATA PAGE 28- VIRTEX-5 BANKS 23,24,25 AND 26

PAGE 29- VIRTEX-5 BANKS 5,6,7,8,27, 29 PAGE 30- VIRTEX-5 MGT I/O AND GND BANKS PAGE 31- VIRTEX-5 VCC +1.0V, +2.5V, +3.3V (EXTRA TOC) PAGE 32- VIRTEX-5 DECOUPLING

70 TI 8:1 ANALOG TO DIGITAL CONVERTER

+3.3V +3.3V

U41

+1.0V_HK 4 IN0 VA 2 MEB_TEMP 5 IN1 R62 VD 13 +3.3V_HK 6 IN2 51 +5V_HK 7 IN3 +12V_HK 8 IN4 +24V_HK 9 HK_ADC_MISO IN5 15 -5V_HK 10 DOUT IN6 -12V_HK 11 0.1uF IN7 C27 C61 1uF C62 1uF

HK_ADC_SCK 16 SCLK AGND 3 HK_ADC_SS_N 1 CS HK_ADC_MOSI 14 DIN DGND 12

J21 1 GND GND GND ADC128S102WGRQV

GND

DE_POWER_EN_FPGA SIDE A

SND15M5R700G J2 J23 MNT2 MNT1 1

+3.3V 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 17 16 PLACEHOLDER 124 R241 SIDESELECT_A_RET SIDESELECT_A_IN TIMETICK_A_RET TIMETICK_A_IN TELEM_A_NEG TELEM_A_POS R240 124 CMD_A_NEG CMD_A_POS

CGND GND 66171-300 7 8 CA AN U21 SIDE B BA EM CO 9 10 11 SND15S5R700G

J3 15 14 13 12 11 10 EMI_COMMON 9 8 7 6 5 4 3 2 1 DE_POWER_EN TIMETICK_B_RET TIMETICK_B_IN TELEM_B_NEG TELEM_B_POS J24 1

CMD_B_NEG CMD_B_POS RS422 TRANSCEIVERS,OPTOCOUPLERS CMD_B_NEG CMD_B_POS CMD_A_NEG CMD_A_POS TELEM_B TELEM_A SPACECRAFT COMMINTERFACE J76 +3.3V

SQ50TP 1

+3.3V

GND

GND HS9-26CLV32RH-Q HS9-26CLV31RH-Q 15 12 9 7 1 4 72

DIN CIN BIN AIN EN EN 10 15 14 12 9 7 6 1 2 4

DIN DIN CIN CIN BIN BIN AIN AIN EN EN U1 U2 GND VDD DO DO CO CO BO BO AO AO DOUT COUT BOUT AOUT GND VDD 8 13 14 11 10 5 6 3 2 16 8 11 5 13 3 16 R74 R71

GND R73 R72 45.3 45.3 +3.3V GND +3.3V

GND C63 CMD_B CMD_A

GND C64 TIMETICK_B_IN TIMETICK_B_RET SIDESELECT_A_RET SIDESELECT_A_IN TIMETICK_A_IN TIMETICK_A_RET 1uF 45.3 45.3 1uF TELEM_B_NEG TELEM_B_POS TELEM_A_NEG TELEM_A_POS R204 R69 R70

GND R63

0 1K 1K 1K

GND R68

8 7 6 5 4 3 2 1 CA4 AN4 AN3 CA3 CA2 AN2 AN1 CA1 HCPL-6751 HPCL_6751 U3 GND NC2 VO1 VO2 VO3 VO4 NC1 VCC

GND C67 10 16 14 13 12 11 9 15 1uF +3.3V

GND

R115 5.1K

R64 5.1K

R65 5.1K +3.3V

R66 5.1K TIMETICK_A_N SIDESELECT_A_N TIMETICK_B_N EXTERNAL CONNECTORS - SXM AND PRTS

TO PREAMP/SDD +5V_SXM -5V TO PRTS AND LIMIT SWITCH

J79 J78 1 1

SQ50TP SQ50TP

J5 J6

1 HV 1 PRT_1P 2 TEC- 2 PRT_1N 3 TEC+ 3 PRT_2P 4 4 PRT_2N 5 PREAMP_TEMP 5 PRT_3P 6 TEC_DIODE 6 PRT_3N J81 7 7 1 8 8 9 9 SQ50TP 10 10 11 11 RADCOVER_LIMITSWITCH 12 12 13 13 J77 FRANGIBOLT_PWR 14 14 1 15 15 J80 SQ50TP 1

SQ50TP

GND GND EMI_COMMON

73 FRANGIBOLT RADIATION COVER RELEASE MECHANISM ACTUATION

+32V MSK5055RHS SWITCHING REGULATOR CONTROLLER

+32V

J26 R118 30K

1 J27 R183 30K

U21 1 V5_FRANG_ON R242 13AN CO16 U21 124 V5_FRANG_ON_2 R243 17AN CO1 12CA EM15 124 R174 BA14

18CA EM20 1K R117 66171-300 R175 BA19 10K 1K R100 66171-300 10K

GND GND

EMI_COMMON GND GND

EMI_COMMON

+32V

J82 +32V 1 J84 SQ50TP SQ50TP Q3 IRHNJ57130 U4 1 D

1 VIN VCC 13 1

2 SHDN C28 BOOST 16

C17 C69 15 0.1uF 2

+ + TG 3 G 47uF 2.2uF CSS 14 SW 3 S 12 5 BG D7 VFB BAS521-7 6 VC SENSE+ 10 9 7 SENSE- C70 SYNC J83 SGND 4 J85 EMI_COMMON 0.0015uF SQ50TP SQ50TP 8 FSET PGND 11

MSK5055-1RHG 1 J86 J28 SQ50TP

1 EMI_COMMON

C65 1 L1 EMI_COMMON R7 1uF 68UH 10m D8 1 D Q4 R82 IRHNJ57130 20K EMI_COMMON FRANGIBOLT_PWR

1 D9 1N4148-1 G R15 C71 C73 3 S

C74 C124 C125 R17 R6 2 B160-13-F 10K 0.0022uF 100pF + + + 71.5K 191K 33uF 33uF 33uF

J87

EMI_COMMON 1 EMI_COMMON SQ50TP

EMI_COMMON

74 D1 1 3

2NC

BAS70-00

D2 3 1 CGND GND NC2

BAS70-00

75 +3.3V +12V +3.3V POWERS +3.3V

J30 1 J31 R208 R196 1 300 +24V 300 U10 6 +12V_HK R86 - 7 5 OUT C87 U11 + 2 of 2 6- +3.3V_HK +5V R80 7 J29 32.4K 5 OUT 1uF C77 LT2078IS8 + 2 of 2 1 8K 1uF

R77 U11 LT2078IS8 8K U10 8V+ GND LT2078IS8 R79 2 8V+ R81 - 1 +5V_HK 8K GND LT2078IS8 OUT 2 3 R61 - + OUT 1 +24V_HK 1 of 2 3 8K 4 + 1 of 2 V- 160K 4 V- R83 GND R78

8K 20K GND

GND

GND GND GND

+1.0V

-12V

5 R85 2 of 2 + +1.0V_HK OUT 7

0 20K

R231 U29

U6 MAX4416ESA R89 6- OUT 7 -12V_HK SEE PAGE 18 FOR 1,2,3 8 AND 4 OP AMP 200K 5 + 2 of 2

LT2078IS8

0 R232

GND

+3.3V

-5V R5

300 C66

R16 1uF

10K

R233 GND

8V+ U6 R84 2- OUT 1 -5V_HK 20K 3 + 1 of 2 4 V- LT2078IS8

R230 GND

GND

4.7K R165 GND

FLASH_RESET_N FLASH_A9 FLASH_A8 FLASH_A7 FLASH_A6 FLASH_A5 FLASH_A4 FLASH_A3 FLASH_A2 FLASH_A1 FLASH_A0 FLASH_WE_N FLASH_OE_N FLASH_CE_N FLASH_A21 FLASH_A20 FLASH_A19 FLASH_A18 FLASH_A17 FLASH_A16 FLASH_A15 FLASH_A14 FLASH_A13 FLASH_A12 FLASH_A11 FLASH_A10 AEROFLEX 64MBITNORFLASH

R235 0 FLASH_WP_N 1uF C68

GND +3.3V

+3.3V

R108

77 4.7K UT8QNF8M8-60XEC 47 12 14 11 28 26 13 10 16 17 48 18 19 20 21 22 23 24 25 9 1 2 3 4 5 6 7 8

BYTE RESET WP WE OE CE A21 A20 A19 A18 A17 A16 A15 A14 A13 A12 A11 A10 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 U5 DQ15/A-1 VSS_2 VSS_1 RY/BY DQ14 DQ13 DQ12 DQ11 DQ10 DQ9 DQ8 DQ7 DQ6 DQ5 DQ4 DQ3 DQ2 DQ1 DQ0 VCC 46 27 15 45 43 41 39 36 34 32 30 44 42 40 38 35 33 31 29 37 +3.3V FLASH_DQ15 FLASH_DQ14 FLASH_DQ13 FLASH_DQ12 FLASH_DQ11 FLASH_DQ10 FLASH_DQ9 FLASH_DQ8 FLASH_DQ7 FLASH_DQ6 FLASH_DQ5 FLASH_DQ4 FLASH_DQ3 FLASH_DQ2 FLASH_DQ1 FLASH_DQ0

GND FLASH_RY_N/BY_N

R166 4.7K

+3.3V PRIMARY POWER

EMI FILTER, +5V, +12V, +24V, -12VDC

+32V +5V +5V

0 R39 DEPOP R40 DEPOP

U15 +5V_PWR 8 +IN +OUT 4 C29 +32V 1 INH NC 2 1uF 7 IN_COM OUT_COM 3

5 SYNC CASE 6 CGND

SMHF2805S/KR

EMI_COMMON CGND J34 1 +32V SQ50TP GND

D5 +12V -12V JANTXV1N5806US

1 2 D6 3

4 D3 C30 0 U16 R88 5 DEPOP

JANTXV1N5806US R101

U14 0

6 R97 1uF 1 +IN +OUT 3 DEPOP JANTXV1N5806US 2 7 1 2 +12V_PWR +VIN +VOUT 8 2 4 D4 5 4 IN_COM OUT_COM 9 INCOM OUTCOM

3 DE_POWER_EN 7 6 -12V_PWR C75 JANTXV1N5806US CASE INH -OUT

SND9M5R600G + J36 22uF 5 SFMC28-461KH CASE_GND 1 EMI_COMMON SQ50TP SLH2812D/KR CGND

+32V CGND GND

+24V

TIE CASES (CHASSIS) OF EMI FILTER AND DC CONVERTERS TOGETHER, AND KEEP TRACES AS SHORT AND WIDE AS POSSIBLE J33 1

SQ50TP

J35 0 DEPOP SQ50TP R129 C31 U17

1 3 1uF 1 +IN +OUT +24V_PWR 2 IN_COM OUT_COM 4

DE_POWER_EN 7 INH -OUT 6 EMI_COMMON

CASE_GND 5

SLH2812D/KR CGND EMI_COMMON GND

78 1.0V POWER

+5V +5V

+1.0V

R187 R188 1 1

L2 +5V

C35 C34 1 2 3

C8 C9 C10 1uF 1uF C78 2.2UH + + + + U12 47uF 47uF 47uF 330uF 4 13 D10 PVIN1_1 DVDD_1 5 14 C5 C6 C7 GND GND C18 C32 C33 PVIN1_2 DVDD_2 MBRS320T3G + + + + 44 PVIN2_1 AVDD 19 GND 47uF 47uF 47uF 45 PVIN2_2 150uF 1uF 1uF 42 PVIN3_1 LX1 3 43 46 PVIN3_2 LX2 +5V 34 41 PVIN4_1 LX3 GND GND 35 PVIN4_2 LX4 36 32 PVIN5_1 LX5 31 33 26 PVIN5_2 LX6 J39 24 PVIN6_1 1 GND PGOOD 11 25 PVIN6_2 REF 20 +5V R116 SQ50TP 22 EN 56.2K DGND_1 15 J37 DGND_2 16 SQ50TP 23 PORSEL AGND_1 17 18

12 AGND_2 1 SS 1 PGND1_1 R90 21 FB PGND1_2 2 C21 47 PGND2_1 1K R107 2.5_SYNC 6 SYNC PGND2_2 48 0.01uF 10.2K PGND3_1 39 7 M/S PGND3_2 40 PGND4_1 37 8 38 ZAP PGND4_2 2.5V_ENABLE PGND5_1 29 30 C20 9 PGND5_2 C3 TDI 27 C1 10 PGND6_1 J38 0.1uF TDO 28 0.22uF 0.01uF GND PGND6_2 SQ50TP

+1.0V 1 ISL70001SRHQF

GND GND GND GND GND

R91 C80 1K 0.0047uF

R109

1.5K

GND

79 2.5V POWER

+5V +5V

+2.5V

R189 R190 1 1

L3 +5V

C36 C37 1 2 3

C14 C13 C12 1uF 1uF C79 2.2UH + + + + U13 47uF 47uF 47uF 330uF 4 13 D21 GND PVIN1_1 DVDD_1 5 14 C16 C15 C11 GND GND C19 C38 C39 PVIN1_2 DVDD_2 MBRS320T3G + + + + 44 PVIN2_1 AVDD 19 47uF 47uF 47uF 45 PVIN2_2 150uF 1uF 1uF 42 PVIN3_1 LX1 3 43 46 PVIN3_2 LX2 34 41 PVIN4_1 LX3 GND GND 35 PVIN4_2 LX4 36 J40 32 31 2.5V_ENABLE SQ50TP PVIN5_1 LX5 33 26 PVIN5_2 LX6 24 PVIN6_1 11 GND PGOOD J42 1 25 PVIN6_2 20 SQ50TP R191 REF +5V 22 499 EN DGND_1 15

DGND_2 16 1 23 PORSEL AGND_1 17 AGND_2 18 12 SS 1 PGND1_1 R93 21 FB PGND1_2 2 47 C23 PGND2_1 1K R94 2.5_SYNC 6 SYNC PGND2_2 48 1K 39 0.01uF PGND3_1 7 M/S PGND3_2 40 PGND4_1 37 8 38 ZAP PGND4_2 3.3V_ENABLE PGND5_1 29 30 C22 9 PGND5_2 C4 TDI J41 C2 PGND6_1 27 10 TDO SQ50TP 0.01uF GND 0.1uF PGND6_2 28 0.22uF

+2.5V 1 ISL70001SRHQF

GND GND GND GND GND

R92 C81

1K 0.0047uF

R182 316

GND

80 +3.3V POWER

+3.3V -5V POWER

+5V

R111 C25 C84 C24

+ C83 + J43 220uF SQ50TP 220uF 0.1uF 4.32K 0.1uF

GND GND U18 GND R18 C72 806 2 VOUT_1 VIN_1 12 3 13 100pF VOUT_2 VIN_2 4 VOUT_3 VIN_3 14 5 VOUT_4 VIN_4 15 6 VOUT_5 VIN_5 16

7 VOUT_6 VIN_6 17 GND GND 11 OCP BYP 9 8 VADJ 3.3V_ENABLE EN 10 18 PG

1 GND

C85 ISL75051SRHQF 5.49K R95 J44 0.18uF R114 SQ50TP 1K

GND GND GND GND

J46 SQ50TP -12V

C40

1uF 0 U20 3 2 R112 R211 VIN OUT C41 DEPOP 357 1 ADJ 1uF GND

RH137H

R113 120 1

J45 SQ50TP

-5V

81 3D-PLUS 1GBIT DDR SDRAM

+2.5V +2.5V

R121

U19 1K

SDRAM_A0 R19 33 29 A0 VDD_1 1 SDRAM_VREF SDRAM_A1 R20 33 30 A1 VDD_2 18 SDRAM_A2 R21 33 31 A2 VDD_3 33 R120 SDRAM_A3 R23 33 32 C86 A3 3 J50 SDRAM_A4 R24 33 35 VDDQ_1 SQ50TP 1K 0.0082uF A4 9 SDRAM_A5 R22 33 36 VDDQ_2 A5 15 SDRAM_A6 R26 33 37 VDDQ_3

A6 55 1 SDRAM_A7 R25 33 38 VDDQ_4 A7 61 SDRAM_A8 R27 33 39 VDDQ_5 A8 SDRAM_CK SDRAM_A9 R29 33 40 49 A9 VREF GND SDRAM_A10 R30 33 28 AP/A10 J47 SDRAM_A11 R28 33 41 2 R48 33 SDRAM_DQ0 SQ50TP A11 DQ0 SDRAM_A12 R31 33 42 A12 DQ1 4 R49 33 SDRAM_DQ1 SDRAM_A13 R32 33 17 A13 DQ2 5 R47 33 SDRAM_DQ2

1 DQ3 7 R51 33 SDRAM_DQ3 SDRAM_BA0 R34 33 26 BA0 DQ4 8 R52 33 SDRAM_DQ4 SDRAM_BA1 R35 33 27 BA1 DQ5 10 R50 33 SDRAM_DQ5 11 R54 33 SDRAM_DQ6 SDRAM_CKE R36 33 44 DQ6 CKE 13 R53 33 SDRAM_DQ7 SDRAM_CK 45 DQ7 CK 54 R55 33 SDRAM_DQ8 SDRAM_CK_N 46 DQ8 100 CK R136 J48 56 R56 33 SDRAM_DQ9 SDRAM_CS_N R67 33 24 DQ9 SQ50TP CS 57 R57 33 SDRAM_DQ10 SDRAM_RAS_N R38 33 23 DQ10 RAS 59 R46 33 SDRAM_DQ11 SDRAM_CAS_N R37 33 22 DQ11

CAS 60 R58 33 SDRAM_DQ12 1 DQ12 SDRAM_WE_N R44 33 21 WE DQ13 62 R45 33 SDRAM_DQ13 63 R59 33 SDRAM_DQ14 SDRAM_CK_N DQ14 DQ15 65 R60 33 SDRAM_DQ15 SDRAM_LDQS SDRAM_LDM R41 33 20 LDM LDQS 16 R33 33 SDRAM_UDM R43 33 47 UDM UDQS 51 R42 33 SDRAM_UDQS J49 34 VSS_1 SQ50TP VSS_2 48 19 DNU_1 VSS_3 66

50 DNU_2 1 VSSQ_1 6 14 NC_1 VSSQ_2 12 25 NC_2 VSSQ_3 52 43 NC_3 VSSQ_4 58 53 NC_4 VSSQ_5 64

3D 1D1G16TS1267MS GND GND

82 MOSFET SWITCH

DECTECTOR ELECTRONICS 5V RAIL

SOLAR X-RAY MONITOR 5V RAIL

+5V +5V_SXM +5V

DEPOP R102 10K

Q1 R215 4 VIN VOUT 1 5V_SXM_ON 0 3 EN GND_1 2 6 NC GND_2 5

MIC94073YC6

R173

4 VIN VOUT 1 R170 3 EN GND_1 2 6 NC GND_2 5 1K

MIC94073YC6

GND

83 SOLAR X-RAY MONITOR DAC & ADC

+3.3V

R164 4.7

C101 C42 10uF 0.1uF

+3.3V +3.3V GND GND

U23 U33 U25 OUTU_1 4 2 SXM_DAC_MOSI 9 1 IN0 VA SXM_DAC_MOSI 9 1 DIN VA PRT_1P 5 DIN VA SXM_DAC_SPCK 8 IN1 13 SXM_DAC_SPCK 8 SCLK PRT_2P 6 VD SCLK SXM_DAC_SYNC_N2 7 4 HVDAC IN2 SXM_DAC_SYNC_N 7 4 VLLD SYNC VOUT SYNC VOUT PRT_3P 7 IN3 2 MEB_TEMP2 8 2 NC_1 IN4

NC_1 1 1 3 PREAMP_TEMP 9 SXM_ADC_MISO 3 J14 NC_2 J7 IN5 15 NC_2 5 TEC_TEMP 10 DOUT 5 NC_3 IN6 NC_3 6 10 HKHV 11 NC_4 GND 1 C103 IN7 6 NC_4 GND 10 1 C102 J10 10uF SXM_ADC_SPCK 16 SCLK 3 J15 10uF AGND DAC121S101WGRLV SXM_ADC_CNV 1 DAC121S101WGRLV CS SXM_ADC_MOSI 14 12 DIN DGND

GND GND

GND ADC128S102WGRQV GND

GND +3.3V

D22

PREAMP_TEMP 1 2

MBRM140T1G

D23

TEC_TEMP 1 2

MBRM140T1G

D24

HKHV 1 2

MBRM140T1G

84 SOLAR X-RAY MONITOR AMPLITUDE CAPTURE

+3.3V

R145 R137 R104 100

1K 10K C43 C51

1uF 1uF

U30 GND GND 6- OUT 7 GND U30 5 8V+ + 2 of 2 VB R180 R119 1K 2- 1 PH+ OUTU_1 MAX4416ESA OUTU R127 1K 3 OUT + 1 of 2 4 22

V- SPARE MAX4416ESA

GND

R138 R103 J16 1

1K 10K C109 1nF

GND GND

85 SOLAR X-RAY MONITOR COCKCROFT WALTON HIGH VOLTAGE GENERATOR

+12V +24V

DEPOP +5V_SXM R144 R244 620 620

R2 D11 470

2 C99 C91

BAV99-TP GND

3 33nF

C44 C45 33nF 1 C100 1uF 1uF

33nF 620 R143 C88 33nF GND D12 HV GND GND C26 2 J12 0.1uF

J13 BAV99-TP C92 3 R123 R124 R147

DEPOP

1 33nF C126 2.55MEG 2.55MEG 49.9K

1 0.1uF C 1 8V+ U7 Q2 R146 R140 HVDAC 2 SXM_CW_PWM C98 - 1 B 4 3 OUT NPN 33nF 49.9K 3 + 1 of 2 U7 NC 4 1K D13 V- 6 LT2078IS8 - 7 HKHV E 2 5 OUT JANTXV2N2222AUA 2 + 2 of 2 C93

BAV99-TP R8 LT2078IS8 3 33nF

1 10K

GND GND

PMBTA92 GND C89 GND 33nF E 2 D14 1

B 2 C 3 Q10

BAV99-TP C94 3

1 33nF GND

C97 33nF D15 R154

1MEG 2 C96 C111

BAV99-TP

3 33nF 47nF

C90 J11 GND 33nF PMBTA92 Q11

D16 1

B 1 R10

2 C E HV

C95 3 2 J51 BAV99-TP 3 33nF SQ50TP 10K

1 R9 C112

47nF

1 10K

HV_CW GND

86 SOLAR X-RAY MONITOR SHAPING AND AMPLIFICATION +3.3V

+3.3V

R192 100

R193 100 C48 J56 SQ50TP VB 1uF

J55 VB C47 R161

SQ50TP 1 1uF GND

R160 1K 1 OUTU

C117 VB GND MAX4416ESA

1K R169 240pF 5 + 2 of 2 R158 R141 C115 249 OUT R150 7 6- 200 100 430pF 332 U31 8V+ U31 2 R155 - 1 R153 3 OUT + 1 of 2 20 J54 8V+ U29 165 4 R139 V- SQ50TP 2- R148 C110 OUT 1 3 R151 MAX4416ESA 11nF + 1 of 2 51.1 1 4 22.1 1K V- C82 MAX4416ESA

3nF GND GND

D17 GND GND J57

SQ50TP 2 R142 C114 U29 PINS 5,6,7 IS ON PAGE PAGE 7 (HK)

BAV99-TP R162 3

100

1.3nF 1 1

1K +5V_SXM OUTB C118

240pF

R157 R163 MAX4416ESA 100 5 + 2 of 2 R149 1K R152 C116 OUT 7 6- GND 51.1 C46 22.1 1.1nF U32 C113 1uF J52 4.3nF SQ50TP R159 2.2K

1 GND GND U28 VCC+ J4 5NC1 7 3+ OUT 6 2- 142-0701-501 J53 1NC 4 SQ50TP 8NC2 VCC-

AD8011AR 1

GND GND

87 SOLAR X-RAY MONITOR TEC DRIVER

+32V

MPZ2012S102A L8

22UH SPD62R-223M

C50 C104 10uF 1uF

EMI_COMMON EMI_COMMON

E 3 J58 SQ50TP 1 B PNP

C 4 Q13 R203 1 3.9K 2SB1316 U21 SXM_TEC_ENABLE R238 L4 3AN CO6 +32_TEC 124 MPZ2012S102A 2CA EM5 4 BA J61

SQ50TP 66171-300

GND 1 EMI_COMMON

D19 MPZ2012S102A

2 1 DEPOP

R98 MBRM140T1G

10K C105 C106 J60 +3.3V +32V 10uF 10uF SQ50TP

1 EMI_COMMON L6

MPZ2012S102A L9 R179 C49 2 D 1uF Q14 30

100UH J18 20K R172 TEC-

IRFL014PBF C107 C108 1 1 GND G 10uF 10uF 14VDD U35 U24 U35 3 S 1 4 R239 A 3 A 6 17 1 2 OUT 5 OUT AN CO B B 124 SXM_TEC_PWM 7GND CD74AC00M96 EMI_COMMON CD74AC00M96 18CA EM20

BA19

66171-300

R1 10K GND U35 12 A 11 13 OUT B CD74AC00M96

+3.3V GND EMI_COMMON

U35

9 J59 U24 A 8 10 OUT R11 10K B SQ50TP 16CO AN13 R171

CD74AC00M96 1 1 15EM CA12

14BA

66171-300

GND

EMI_COMMON

88 SOLAR X-RAY MONITOR TEC TEMPERATURE INTERFACE

+5V_SXM

R87

470

C53

1uF

R12

10K GND

R177

24.9K

GND U8 V+8 R13 2 TEC_DIODE 1 - OUT 3 1 of 2 + 10K 4 V- LT2078IS8 +5V_SXM

GND R3 J63 470 SQ50TP

1 C52 +1.0V TEC_DIODE 1uF

J62

SQ50TP J32 GND +2.5V +2.5V 1

1 8V+ U9 U8 2 R14 R178 - 1 TEC_TEMP 6 3 OUT U9 - 7 OUT + 1 of 2 6 5 - 7 +1.0V_HK + R125 4 5 OUT 2 of 2 V- 10K 24.9K + 2 of 2 LT2078IS8 LT2078IS8 82.5K LT2078IS8

GND

R126 R181

22.6K 100K

GND

89 SOLAR X-RAY MONITOR THRESHOLD CONTROL

+3.3V

R96 1K

C120 47uF

GND VB

D18

3 BAV99-TP C55 1uF

GND GND

SOLAR X-RAYMONITORTRIGGERANDTIMING VLLD SQ50TP OUTB VB ZLE J64 J66 1 SQ50TP

J65

1 SQ50TP

GND

GND MAX961ESA 3 2 1 4

SHDN IN- IN+ LE MAX961ESA 3 2 1 4

SHDN IN- IN+ LE U38 91 U39 R194 GND VCC 30 Q Q +3.3V R195 5 7 6 8 GND VCC 30 Q Q +3.3V GND 5 7 6 8

GND GND

GND 1uF C56

1uF C57

J20 1

ZP J19 1

LLD PRT TEMPERATURE MEASUREMENT INTERFACE

+3.3V +3.3V +5V +5V +3.3V

R185 R205 200 R206 200 200

PRT_1P U27 PRT_2P U26 PRT_3P R249 1 2 MEB_TEMP2 R248 + - 1 2 MEB_TEMP 1.15K + - PRT_1N NC 3 PRT_2N 3 1.15K PRT_3N NC R186 R133 200 R207 AD590LH 200 AD590LH 200 R167 2.2K R76 2.2K

GND GND GND GND GND

92 VIRTEX-5 BANKS 0-4 CONFIGURATION ADDRESS OSCILLATOR

+3.3V +3.3V

+2.5V +3.3V +3.3V +3.3V

R201 R200 4.7K 4.7K

R197 4.7K U22 R236 R237 4.7K +3.3V AC22 Y22 +3.3V 4.7K DXP_0 BANK 0 - 4 AVDD_0 J67 AC21 Y21 DXN_0 AVSS_0 SQ50TP R246 AA22 VP_0 VBATT_0 P30 R245 AB21 4.7K 100 VN_0 VREFP_0 AB22 1 R29 AA21 R198 PROGRAM_B_0 VREFN_0 R105 P15 HSWAPEN_0 J8 4.7K 4.7K R15 D_IN_0 R199 INIT_B_0 T14 1 T30 CS_B_0 D_OUT_BUSY_0 AJ16 4.7K 2 R30 RDWR_B_0 DONE_0 R14 3 R106 4.7K AH29 M0_0 CCLK_0 AH14 4 TMS_0 AH30 M1_0 5 R99 4.7K AJ28 V31 TCK_0 M2_0 RSVD_1 6 AF30

RSVD_2 7 TCK_0 AG29 TCK_0 +3.3V 100 R247 8 TDO_0 TDI_0 AH16 TDI_0 9 TDO_0 AJ15 TDO_0 10 TDI_0 TMS_0 AH15 TMS_0 +3.3V 11 J16 FLASH_A19 N25 IO_L0P_CC_GC_3 12 IO_L0P_A19_1 J15 FLASH_A18 P25 IO_L0N_CC_GC_3 GND 13 IO_L0N_A18_1 M26 FLASH_A17 P18 IO_L1P_CC_GC_3 14 GND IO_L1P_A17_1 L27 +3.3V FLASH_A16 P17 IO_L1N_CC_GC_3 IO_L1N_A16_1 J17 FLASH_A15 P26 IO_L2P_GC_VRN_3 87833-1421 IO_L2P_A15_D31_1 K17 4 U42 FLASH_A14 N26 IO_L2N_GC_VRP_3 VCC IO_L2N_A14_D30_1 M27 1 1116R36M00000BF FLASH_A13 M16 IO_L3P_GC_3 E_D 3 GND IO_L3P_A13_D29_1 M28 OUT FLASH_A12 N16 IO_L3N_GC_3 IO_L3N_A12_D28_1 L17 2 FLASH_A11 P27 IO_L4P_GC_3 GND IO_L4P_A11_D27_1 M17 R110 R130 R4 R122 FLASH_A10 P28 IO_L4N_GC_VREF_3 IO_L4N_VREF_A10_D26_1 L29 4.7K 4.7K 4.7K 4.7K FLASH_A9 N15 IO_L5P_GC_3 IO_L5P_A9_D25_1 K28 R202 C121 FLASH_A8 N14 IO_L5N_GC_3 IO_L5N_A8_D24_1 L16 4.7K R134 FLASH_A7 N28 IO_L6P_GC_3 IO_L6P_A7_D23_1 L15 0.1uF 30.1 FLASH_A6 N29 IO_L6N_GC_3 IO_L6N_A6_D22_1 K29 FLASH_A5 M14 IO_L7P_GC_3 IO_L7P_A5_D21_1 J30 FLASH_A4 M13 IO_L7N_GC_3 GND IO_L7N_A4_D20_1 L14 FLASH_A3 N30 IO_L8P_GC_3 IO_L8P_CC_A3_D19_1 K15 FLASH_A2 M29 IO_L8N_GC_3 GND GND IO_L8N_CC_A2_D18_1 K30 FLASH_A1 N13 IO_L9P_GC_3 IO_L9P_CC_A1_D17_1 L30 IO_L9N_GC_3 IMPEDANCE CONTROL 50 OHM FLASH_A0 P13 IO_L9N_CC_A0_D16_1 AN30 FLASH_DQ15 AK12 IO_L0P_GC_D15_4 IO_L0P_CC_RS1_2 AP30 FLASH_DQ14 AK13 IO_L0N_GC_D14_4 IO_L0N_CC_RS0_2 AK17 FLASH_DQ13 AJ30 IO_L1P_GC_D13_4 IO_L1P_CC_A25_2 AL17 FLASH_DQ12 AK30 IO_L1N_GC_D12_4 IO_L1N_CC_A24_2 AN29 FLASH_DQ11 AK15 IO_L2P_GC_D11_4 IO_L2P_A23_2 AP28 FLASH_DQ10 AK14 IO_L2N_GC_D10_4 +3.3V IO_L2N_A22_2 AL15 FLASH_DQ9 FLASH_A21 AL30 IO_L3P_GC_D9_4 IO_L3P_A21_2 AL16 FLASH_DQ8 FLASH_A20 AM29 IO_L3N_GC_D8_4 IO_L3N_A20_2 AP27 R128 FLASH_CE_N AL14 IO_L4P_GC_4 IO_L4P_FCS_B_2 AN28 FLASH_OE_N AM13 IO_L4N_GC_VREF_4 IO_L4N_VREF_FOE_B_MOSI_2 AM16 FLASH_RY_N/BY_N FLASH_WE_N AM28 IO_L5P_GC_4 IO_L5P_FWE_B_2 AM17 FLASH_WP_N 4.7K AL29 IO_L5N_GC_4 IO_L5N_CSO_B_2 AM27 R156 R132 FLASH_DQ7 AN13 IO_L6P_GC_4 R131 IO_L6P_D7_2 AM26 4.7K FLASH_DQ6 AP13 IO_L6N_GC_4 4.7K 4.7K IO_L6N_D6_2 AN15 FLASH_DQ5 AK28 IO_L7P_GC_VRN_4 GND IO_L7P_D5_2 AN16 FLASH_DQ4 AK29 IO_L7N_GC_VRP_4 IO_L7N_D4_2 AL27 FLASH_DQ3 AN14 IO_L8P_CC_GC_4 IO_L8P_D3_2 AL26 FLASH_DQ2 AM14 IO_L8N_CC_GC_4 IO_L8N_D2_FS2_2 AP16 IO_L9P_CC_GC_4 J69 FLASH_DQ1 AK27 IO_L9P_D1_FS1_2 IO_L9N_CC_GC_4 AP15 FLASH_DQ0 AJ26 IO_L9N_D0_FS0_2 SQ50TP

XQ5VFX130T-1EF1738I 1

GND GND

93 VIRTEX-5 BANKS 11,12,13 AND 15

U22

BANK 31 - 34 D20 NC_1 NC_61 AV28 D21 NC_2 NC_62 AW27 C21 NC_3 NC_63 AV26 C20 NC_4 NC_64 AW26 A20 NC_5 NC_65 BB22 U22 A21 NC_6 NC_66 BB23 U22 A22 NC_7 NC_67 BB21 B21 BA22 F42 AA7 NC_8 NC_68 IO_L0P_11 BANK 11 - 12 IO_L0P_12 AB41 BANK 13 - 15 H38 D22 AY22 G42 AA6 IO_L0P_SM8P_13 IO_L0P_15 NC_9 NC_69 IO_L0N_11 IO_L0N_12 AB42 H39 D23 AY23 F41 G6 IO_L0N_SM8N_13 IO_L0N_15 NC_10 NC_70 IO_L1P_11 IO_L1P_12 AC41 G38 C23 AW23 G41 H5 IO_L1P_SM7P_13 IO_L1P_15 NC_11 NC_71 IO_L1N_11 IO_L1N_12 AD42 G39 B22 AW22 H41 W5 IO_L1N_SM7N_13 IO_L1N_15 NC_12 NC_72 IO_L2P_11 IO_L2P_12 AE42 F39 B23 BB20 J41 W6 IO_L2P_SM6P_13 IO_L2P_15 NC_13 NC_73 IO_L2N_11 IO_L2N_12 AD41 F40 A24 BA21 J42 H6 IO_L2N_SM6N_13 IO_L2N_15 NC_14 NC_74 IO_L3P_11 IO_L3P_12 AF41 E39 B24 BA20 K42 J5 IO_L3P_SM5P_13 IO_L3P_15 NC_15 NC_75 IO_L3N_11 IO_L3N_12 AF42 E40 C24 BA19 L40 Y7 IO_L3N_SM5N_13 IO_L3N_15 NC_16 NC_76 IO_L4P_11 IO_L4P_12 AF40 R39 E24 AY19 L41 W7 IO_L4P_13 IO_L4P_15 NC_17 NC_77 IO_L4N_VREF_11 IO_L4N_VREF_12 AG41 R38 E25 AY20 L42 J6 IO_L4N_VREF_13 IO_L4N_VREF_15 NC_18 NC_78 IO_L5P_11 IO_L5P_12 AG42 R37 D25 AW21 M41 K5 IO_L5P_SM4P_13 IO_L5P_15 NC_19 NC_79 IO_L5N_11 IO_L5N_12 AH41 P37 D26 AW20 M42 W8 IO_L5N_SM4N_13 IO_L5N_15 NC_20 NC_80 IO_L6P_11 IO_L6P_12 AJ42 P38 E28 N41 V8 IO_L6P_SM3P_13 IO_L6P_15 NC_21 AW18 IO_L6N_11 IO_L6N_12 AJ41 N38 E27 NC_81 N40 K4 IO_L6N_SM3N_13 IO_L6N_15 NC_22 AV19 IO_L7P_11 IO_L7P_12 AH40 N39 D27 NC_82 P40 L5 IO_L7P_SM2P_13 IO_L7P_15 NC_23 AL11 IO_L7N_11 IO_L7N_12 AJ40 M39 C26 NC_83 W40 V5 IO_L7N_SM2N_13 IO_L7N_15 NC_24 AL12 IO_L8P_CC_11 IO_L8P_CC_12 AB37 M38 C25 NC_84 Y40 V6 IO_L8P_CC_SM1P_13 IO_L8P_CC_15 NC_25 AV18 IO_L8N_CC_11 IO_L8N_CC_12 AB38 L39 B26 NC_85 AA40 L6 IO_L8N_CC_SM1N_13 IO_L8N_CC_15 NC_26 AU17 IO_L9P_CC_11 IO_L9P_CC_12 AB39 K38 A26 NC_86 AA39 M6 IO_L9P_CC_SM0P_13 IO_L9P_CC_15 NC_27 AM11 IO_L9N_CC_11 IO_L9N_CC_12 AC38 J38 A25 NC_87 Y39 N5 IO_L9N_CC_SM0N_13 IO_L9N_CC_15 NC_28 AM12 IO_L10P_CC_SM15P_11 IO_L10P_CC_12 AE40 H40 A27 NC_88 Y38 N6 IO_L10P_CC_13 IO_L10P_CC_15 NC_29 AV16 IO_L10N_CC_SM15N_11 IO_L10N_CC_12 AD40 J40 B27 NC_89 Y37 U7 IO_L10N_CC_13 IO_L10N_CC_15 NC_30 AU16 IO_L11P_CC_SM14P_11 IO_L11P_CC_12 AC40 K40 B28 NC_90 AA37 U6 IO_L11P_CC_13 IO_L11P_CC_15 NC_31 AN11 IO_L11N_CC_SM14N_11 IO_L11N_CC_12 AC39 K39 A29 NC_91 R42 P5 IO_L11N_CC_13 IO_L11N_CC_15 NC_32 AN10 IO_L12P_VRN_11 IO_L12P_VRN_12 AK40 V38 F30 NC_92 P42 P6 IO_L12P_VRN_13 IO_L12P_VRN_15 NC_33 AV15 IO_L12N_VRP_11 IO_L12N_VRP_12 AL40 U37 E30 NC_93 P41 T7 IO_L12N_VRP_13 IO_L12N_VRP_15 NC_34 AV14 IO_L13P_11 IO_L13P_12 AL41 T37 E29 NC_94 R40 T6 IO_L13P_13 IO_L13P_15 NC_35 AP10 IO_L13N_11 IO_L13N_12 AK42 U38 D30 NC_95 T40 R4 IO_L13N_13 IO_L13N_15 NC_36 AR9 IO_L14P_11 IO_L14P_12 AL42 T39 C29 NC_96 T41 R5 IO_L14P_13 IO_L14P_15 NC_37 AW13 IO_L14N_VREF_11 IO_L14N_VREF_12 AM42 U39 B29 NC_97 T42 T5 IO_L14N_VREF_13 IO_L14N_VREF_15 NC_38 AV13 IO_L15P_SM13P_11 IO_L15P_12 AM41 V39 C28 NC_98 U41 T4 IO_L15P_13 IO_L15P_15 NC_39 AP11 IO_L15N_SM13N_11 IO_L15N_12 AN41 W38 D28 NC_99 U42 AA11 IO_L15N_13 IO_L15N_15 NC_40 AP12 IO_L16P_SM12P_11 IO_L16P_12 AP42 AA35 NC_100 V41 AA10 IO_L16P_13 IO_L16P_15 BB29 AR10 IO_L16N_SM12N_11 IO_L16N_12 AP41 AA36 NC_41 NC_101 V40 AA9 IO_L16N_13 IO_L16N_15 BB28 AT10 IO_L17P_SM11P_11 IO_L17P_12 AR42 AA34 NC_42 NC_102 W41 Y10 IO_L17P_13 IO_L17P_15 BB27 AW12 IO_L17N_SM11N_11 IO_L17N_12 AT42 Y34 NC_43 NC_103 W42 W11 IO_L17N_13 IO_L17N_15 BA27 AV11 IO_L18P_SM10P_11 IO_L18P_12 AT41 Y35 NC_44 NC_104 Y42 W10 IO_L18P_13 IO_L18P_15 BB26 AT11 IO_L18N_SM10N_11 IO_L18N_12 AU41 W35 NC_45 NC_105 AA42 Y9 IO_L18N_13 IO_L18N_15 BA26 AR12 IO_L19P_SM9P_11 IO_L19P_12 AU42 W36 NC_46 NC_106 AA41 Y8 IO_L19P_13 IO_L19P_15 BA25 AU11 IO_L19N_SM9N_11 IO_L19N_12 AV41 W37 NC_47 NC_107 IO_L19N_13 IO_L19N_15 AY25 AU12 NC_48 NC_108 XQ5VFX130T-1EF1738I AW30 NC_49 NC_109 AR13 XQ5VFX130T-1EF1738I AV30 NC_50 NC_110 AT12 AV29 NC_51 NC_111 AU14 AW28 NC_52 NC_112 AU13 AY27 NC_53 NC_113 AW7 AY28 AV8 NC_54 NC_114 AY29 AV10 GND GND NC_55 NC_115 GND GND BA29 NC_56 NC_116 AV9 BB24 NC_57 NC_117 AU9 BA24 NC_58 NC_118 AT9 AY24 NC_59 NC_119 AU8 AW25 NC_60 NC_120 AU7

XQ5VFX130T-1EF1738I

GND GND

94 VIRTEX-5 BANKS 17, 18 AND 19

DETECTOR ELECTRONICS CAMERA LINK INTERFACE NOT CONNECTED (FORMER CONNECTION TO J9)

+12V

+3.3V

U22 -12V BANK 17 - 19 AB34 IO_L0P_17 IO_L10P_CC_18 AC5 AC34 IO_L0N_17 IO_L10N_CC_18 AC6 AC35 IO_L1P_17 IO_L11P_CC_18 AF5 AB36 AF6 +24V IO_L1N_17 IO_L11N_CC_18 AC36 IO_L2P_17 IO_L12P_VRN_18 AD6 AD35 IO_L2N_17 IO_L12N_VRP_18 AD7 AD36 AG6 CAMLINK_SERTFGP +5V IO_L3P_17 IO_L13P_18 AD37 IO_L3N_17 IO_L13N_18 AG7 CAMLINK_SERTFGN AE37 IO_L4P_17 IO_L14P_18 AE5 AD38 IO_L4N_VREF_17 IO_L14N_VREF_18 AD5 AE39 IO_L5P_17 IO_L15P_18 AF7 CAMLINK_X1P AE38 IO_L5N_17 IO_L15N_18 AE7 CAMLINK_X1N AF39 IO_L6P_17 IO_L16P_18 AD8 R217 AG38 IO_L6N_17 IO_L16N_18 AE8 4.7K AG37 IO_L7P_17 IO_L17P_18 AF9 J9 AF37 IO_L7N_17 IO_L17N_18 AF10 AN40 AE9 CAMLINK_X2P 1 IO_L8P_CC_17 IO_L18P_18 AP40 AE10 CAMLINK_X2N 2 IO_L8N_CC_17 IO_L18N_18 AR40 AF11 3 CAMLINK_SERTFGN IO_L9P_CC_17 IO_L19P_18 AT40 AF12 4 IO_L9N_CC_17 IO_L19N_18 GND CAMLINK_SERTCN AV40 5 IO_L10P_CC_17 R34 AU39 IO_L0P_19 6 IO_L10N_CC_17 P35 CAMLINK_X3N AT39 IO_L0N_19 7 IO_L11P_CC_17 N35 AR39 IO_L1P_19 8 IO_L11N_CC_17 M36 CAMLINK_XCLKN AG39 IO_L1N_19 9 IO_L12P_VRN_17 L37 AH39 IO_L2P_19 10 IO_L12N_VRP_17 M37 CAMLINK_X2N AJ38 IO_L2N_19 11 IO_L13P_17 N36 AK39 IO_L3P_19 12 IO_L13N_17 P36 CAMLINK_X1N AK38 IO_L3N_19 13 IO_L14P_17 L36 AK37 IO_L4P_19 14 IO_L14N_VREF_17 L35 CAMLINK_X0N AJ37 IO_L4N_VREF_19 15 IO_L15P_17 K35 CLINK_RESET_N AH38 IO_L5P_19 16 IO_L15N_17 J35 AL39 IO_L5N_19 17 IO_L16P_17 H35 CAMLINK_SERTFGP AM39 IO_L6P_19 18 IO_L16N_17 J36 AN39 IO_L6N_19 19 IO_L17P_17 K37 CAMLINK_SERTCP AP38 IO_L7P_19 20 IO_L17N_17 J37 AN38 IO_L7N_19 21 IO_L18P_17 U34 CAMLINK_X3P AM38 IO_L8P_CC_19 22 IO_L18N_17 T35 AM37 IO_L8N_CC_19 23 IO_L19P_17 T34 CAMLINK_XCLKP AL37 IO_L9P_CC_19 24 IO_L19N_17 IO_L9N_CC_19 U33 25 CAMLINK_SERTCP AJ7 IO_L0P_18 IO_L10P_CC_19 R35 26 CAMLINK_X2P CAMLINK_SERTCN AK7 IO_L0N_18 IO_L10N_CC_19 T36 27 AB11 IO_L1P_18 IO_L11P_CC_19 U36 28 CAMLINK_X1P AC10 IO_L1N_18 IO_L11N_CC_19 V36 29 CAMLINK_X0P AL5 H36 CAMLINK_X0P IO_L2P_18 IO_L12P_VRN_19 30 CAMLINK_X0N AK5 G37 IO_L2N_18 IO_L12N_VRP_19 AB9 F36 J70 IO_L3P_18 IO_L13P_19 AB8 G36 SQ50TP IO_L3N_18 IO_L13N_19 AJ6 IO_L4P_18 IO_L14P_19 F37 AJ5 IO_L4N_VREF_18 IO_L14N_VREF_19 E37

1 CAMLINK_X3P AC8 IO_L5P_18 IO_L15P_19 E38 CAMLINK_X3N AC9 IO_L5N_18 IO_L15N_19 D37 R216 AH6 IO_L6P_18 IO_L16P_19 V35 4.7K AH5 IO_L6N_18 IO_L16N_19 V34 AD10 IO_L7P_18 IO_L17P_19 V33 AD11 W33 IO_L7N_18 IO_L17N_19 CAMLINK_XCLKP AG4 IO_L8P_CC_18 IO_L18P_19 Y33 GND CAMLINK_XCLKN AH4 IO_L8N_CC_18 IO_L18N_19 W32 AB7 IO_L9P_CC_18 IO_L19P_19 Y32 AB6 AA32 J71 IO_L9N_CC_18 IO_L19N_19 SQ50TP GND XQ5VFX130T-1EF1738I

GND

95 VIRTEX-5 BANKS 20 AND 21

DDR SDRAM DATA

U22

BANK 20 - 21 SDRAM_DQ0 N9 IO_L0P_20 IO_L0P_21 AB33 SDRAM_DQ1 N8 IO_L0N_20 IO_L0N_21 AB32 SDRAM_DQ2 E9 IO_L1P_20 IO_L1P_21 AC33 SDRAM_DQ3 E8 IO_L1N_20 IO_L1N_21 AD32 SDRAM_DQ4 P7 IO_L2P_20 IO_L2P_21 AD33 SDRAM_DQ5 P8 IO_L2N_20 IO_L2N_21 AE32 SDRAM_DQ6 D7 IO_L3P_20 IO_L3P_21 AE33 SDRAM_DQ7 E7 IO_L3N_20 IO_L3N_21 AE34 R7 IO_L4P_20 IO_L4P_21 AV39 SDRAM_VREF R8 IO_L4N_VREF_20 IO_L4N_VREF_21 AV38 SDRAM_DQ8 F7 IO_L5P_20 IO_L5P_21 AU38 SDRAM_DQ9 F6 IO_L5N_20 IO_L5N_21 AU37 SDRAM_DQ10 R9 IO_L6P_20 IO_L6P_21 AT37 SDRAM_DQ11 T9 IO_L6N_20 IO_L6N_21 AR38 SDRAM_DQ12 E5 IO_L7P_20 IO_L7P_21 AR37 SDRAM_DQ13 F5 IO_L7N_20 IO_L7N_21 AT36 SDRAM_DQ14 V9 IO_L8P_CC_20 IO_L8P_CC_21 AE35 SDRAM_DQ15 V10 IO_L8N_CC_20 IO_L8N_CC_21 AF34 SDRAM_UDQS F9 IO_L9P_CC_20 IO_L9P_CC_21 AF35 SDRAM_UDM G9 IO_L9N_CC_20 IO_L9N_CC_21 AF36 SDRAM_LDQS G7 IO_L10P_CC_20 IO_L10P_CC_21 AH34 SDRAM_LDM G8 IO_L10N_CC_20 IO_L10N_CC_21 AG34 R221 4.7K U8 IO_L11P_CC_20 IO_L11P_CC_21 AH35 R220 4.7K U9 IO_L11N_CC_20 IO_L11N_CC_21 AG36 H8 IO_L12P_VRN_20 IO_L12P_VRN_21 AP37 H9 IO_L12N_VRP_20 IO_L12N_VRP_21 AP36 T10 IO_L13P_20 IO_L13P_21 AP35 T11 IO_L13N_20 IO_L13N_21 AN36 J8 IO_L14P_20 IO_L14P_21 AM36 J7 IO_L14N_VREF_20 IO_L14N_VREF_21 AN35 U11 IO_L15P_20 IO_L15P_21 AN34 V11 IO_L15N_20 IO_L15N_21 AM34 K8 IO_L16P_20 IO_L16P_21 AH36 K9 IO_L16N_20 IO_L16N_21 AJ36 K7 IO_L17P_20 IO_L17P_21 AJ35 L7 IO_L17N_20 IO_L17N_21 AK35 M7 IO_L18P_20 IO_L18P_21 AL36 M8 IO_L18N_20 IO_L18N_21 AL35 M9 IO_L19P_20 IO_L19P_21 AL34 L9 IO_L19N_20 IO_L19N_21 AK34

XQ5VFX130T-1EF1738I

GND GND

GND

96 VIRTEX-5 BANKS 23,24,25 AND 26

DDR SDRAM ADDRESS/CONTROL

U22

U22 BANK 23 - 24 N33 IO_L0P_23 IO_L0P_24 J12 SDRAM_A0 N34 H11 SDRAM_A1 IO_L0N_23 IO_L0N_24 AG31 BANK 25 - 26 AT7 M34 G12 SDRAM_A2 IO_L0P_25 IO_L0P_26 IO_L1P_23 IO_L1P_24 AF31 AR7 M33 G11 SDRAM_A3 IO_L0N_25 IO_L0N_26 IO_L1N_23 IO_L1N_24 AF32 AG12 M32 F12 SDRAM_A4 IO_L1P_25 IO_L1P_26 IO_L2P_23 IO_L2P_24 AG33 AG11 M31 F11 SDRAM_A5 IO_L1N_25 IO_L1N_26 IO_L2N_23 IO_L2N_24 AH33 AT6 N31 E10 SDRAM_A6 IO_L2P_25 IO_L2P_26 IO_L3P_23 IO_L3P_24 AG32 AR5 P31 F10 SDRAM_A7 IO_L2N_25 IO_L2N_26 IO_L3N_23 IO_L3N_24 AH31 AG9 H34 K14 SDRAM_A8 IO_L3P_25 IO_L3P_26 IO_L4P_23 IO_L4P_24 AJ31 AH9 G34 K13 IO_L3N_25 IO_L3N_26 IO_L4N_VREF_23 IO_L4N_VREF_24 AV35 AT5 G33 K12 SDRAM_A9 IO_L4P_25 IO_L4P_26 IO_L5P_23 IO_L5P_24 AV36 AU6 H33 J11 SDRAM_A10 IO_L4N_VREF_25 IO_L4N_VREF_26 IO_L5N_23 IO_L5N_24 AU36 AH10 SDRAM_VREF IO_L5P_25 IO_L5P_26 G32 IO_L6P_23 IO_L6P_24 J13 SDRAM_A11 AT35 IO_L5N_25 IO_L5N_26 AH11 G31 IO_L6N_23 IO_L6N_24 H13 SDRAM_A12 AU34 IO_L6P_25 IO_L6P_26 AV6 H31 IO_L7P_23 IO_L7P_24 H10 SDRAM_A13 AT34 IO_L6N_25 IO_L6N_26 AV5 J31 IO_L7N_23 IO_L7N_24 J10 AR35 IO_L7P_25 IO_L7P_26 AJ11 F35 IO_L8P_CC_23 IO_L8P_CC_24 H14 SDRAM_CK AR34 IO_L7N_25 IO_L7N_26 AJ10 E35 IO_L8N_CC_23 IO_L8N_CC_24 H15 AU32 IO_L8P_CC_25 IO_L8P_CC_26 AM9 E34 IO_L9P_CC_23 IO_L9P_CC_24 K10 SDRAM_CK_N AU33 IO_L8N_CC_25 IO_L8N_CC_26 AN9 F34 IO_L9N_CC_23 IO_L9N_CC_24 L10 SDRAM_BA0 AV33 IO_L9P_CC_25 IO_L9P_CC_26 AG8 F31 IO_L10P_CC_23 IO_L10P_CC_24 L12 SDRAM_BA1 AV34 IO_L9N_CC_25 IO_L9N_CC_26 AH8 F32 IO_L10N_CC_23 IO_L10N_CC_24 L11 SDRAM_CKE AV31 IO_L10P_CC_25 IO_L10P_CC_26 AK8 E32 IO_L11P_CC_23 IO_L11P_CC_24 G13 AU31 IO_L10N_CC_25 IO_L10N_CC_26 AJ8 E33 IO_L11N_CC_23 IO_L11N_CC_24 G14 AT32 IO_L11P_CC_25 IO_L11P_CC_26 AN8 L34 IO_L12P_VRN_23 IO_L12P_VRN_24 M11 AT31 IO_L11N_CC_25 IO_L11N_CC_26 AP8 K34 IO_L12N_VRP_23 IO_L12N_VRP_24 M12 AP31 IO_L12P_VRN_25 IO_L12P_VRN_26 AK9 K33 IO_L13P_23 IO_L13P_24 F14 AN31 IO_L12N_VRP_25 IO_L12N_VRP_26 AK10 J33 IO_L13N_23 IO_L13N_24 E13 AR32 IO_L13P_25 IO_L13P_26 AP7 K32 IO_L14P_23 IO_L14P_24 N11 AP32 IO_L13N_25 IO_L13N_26 AR8 J32 IO_L14N_VREF_23 IO_L14N_VREF_24 P12 AR33 IO_L14P_25 IO_L14P_26 AL9 L32 IO_L15P_23 IO_L15P_24 E12 SDRAM_CAS_N AP33 IO_L14N_VREF_25 IO_L14N_VREF_26 AL10 L31 IO_L15N_23 IO_L15N_24 D12 SDRAM_WE_N AN33 IO_L15P_25 IO_L15P_26 AP6 P33 IO_L16P_23 IO_L16P_24 P11 SDRAM_CS_N AM33 IO_L15N_25 IO_L15N_26 AP5 P32 IO_L16N_23 IO_L16N_24 N10 SDRAM_RAS_N AK33 IO_L16P_25 IO_L16P_26 AL6 R33 IO_L17P_23 IO_L17P_24 D13 AJ33 IO_L16N_25 IO_L16N_26 AL7 R32 IO_L17N_23 IO_L17N_24 E14 AJ32 IO_L17P_25 IO_L17P_26 AN4 T32 IO_L18P_23 IO_L18P_24 R10 AK32 IO_L17N_25 IO_L17N_26 AN5 U32 IO_L18N_23 IO_L18N_24 P10 AL32 IO_L18P_25 IO_L18P_26 AN6 U31 IO_L19P_23 IO_L19P_24 E15 AM32 IO_L18N_25 IO_L18N_26 AM6 T31 IO_L19N_23 IO_L19N_24 F15 AL31 IO_L19P_25 IO_L19P_26 AM7 AM31 IO_L19N_25 IO_L19N_26 AM8 XQ5VFX130T-1EF1738I

XQ5VFX130T-1EF1738I

GND GND

97 +3.3V

VIRTEX-5 BANKS 5,6,7,8,27, 29

3.3V I/O

+3.3V

U22 U22 U22

CMD_A D31 BANK 27 - 29 AY42 L24 BANK 5 - 6 AR29 M23 BANK 7 - 8 AL21 +3.3V IO_L0P_27 IO_L0P_29 IO_L0P_5 IO_L0P_6 IO_L0P_7 IO_L0P_8 TELEM_A C31 IO_L0N_27 IO_L0N_29 AW42 M24 IO_L0N_5 IO_L0N_6 AR28 M22 IO_L0N_7 IO_L0N_8 AL22 CMD_B C30 IO_L1P_27 IO_L1P_29 AW41 E18 IO_L1P_5 IO_L1P_6 AT14 M21 IO_L1P_7 IO_L1P_8 AK23 TELEM_B B31 IO_L1N_27 IO_L1N_29 AW40 E17 IO_L1N_5 IO_L1N_6 AR14 L21 IO_L1N_7 IO_L1N_8 AK22 DE_POWER_EN_FPGA A30 IO_L2P_27 IO_L2P_29 AY40 K24 IO_L2P_5 IO_L2P_6 AR30 N24 IO_L2P_7 IO_L2P_8 AJ22 SIDESELECT_A_N A31 IO_L2N_27 IO_L2N_29 BA41 L25 IO_L2N_5 IO_L2N_6 AT30 N23 IO_L2N_7 IO_L2N_8 AJ21 TIMETICK_A_N A32 IO_L3P_27 IO_L3P_29 BA42 F16 IO_L3P_5 IO_L3P_6 AT15 N22 IO_L3P_7 IO_L3P_8 AK20 TIMETICK_B_N B32 IO_L3N_27 IO_L3N_29 BB41 F17 IO_L3N_5 IO_L3N_6 AR15 N21 IO_L3N_7 IO_L3N_8 AL20 HK_ADC_MOSI B33 IO_L4P_27 IO_L4P_29 BA40 K25 IO_L4P_5 IO_L4P_6 AT29 H21 IO_L4P_7 IO_L4P_8 AU26 R168 4.7K C33 IO_L4N_VREF_27 IO_L4N_VREF_29 BB39 J25 IO_L4N_VREF_5 IO_L4N_VREF_6 AU29 J21 IO_L4N_VREF_7 IO_L4N_VREF_8 AU27 HK_ADC_MISO D32 IO_L5P_27 IO_L5P_29 BB38 G16 IO_L5P_5 IO_L5P_6 AT17 J20 IO_L5P_7 IO_L5P_8 AU19 D33 IO_L5N_27 IO_L5N_29 BA39 H16 IO_L5N_5 IO_L5N_6 AT16 K20 IO_L5N_7 IO_L5N_8 AU18 HK_ADC_SS_N C34 IO_L6P_27 IO_L6P_29 AY38 H26 IO_L6P_5 IO_L6P_6 AU28 L22 IO_L6P_7 IO_L6P_8 AR25 5V_SXM_ON B34 AW37 J26 AT27 K23 AT25 R213 IO_L6N_27 IO_L6N_29 IO_L6N_5 IO_L6N_6 IO_L6N_7 IO_L6N_8 ZP A34 IO_L7P_27 IO_L7P_29 AW38 G18 IO_L7P_5 IO_L7P_6 AP17 K22 IO_L7P_7 IO_L7P_8 AR20 4.7K SXM_ADC_MISO A35 IO_L7N_27 IO_L7N_29 AY39 G17 IO_L7N_5 IO_L7N_6 AR17 J22 IO_L7N_7 IO_L7N_8 AT20 SXM_ADC_SPCK D35 IO_L8P_CC_27 IO_L8P_CC_29 BB37 J28 IO_L8P_CC_5 IO_L8P_CC_6 AT26 F22 IO_L8P_CC_7 IO_L8P_CC_8 AT24 HK_ADC_SCK D36 IO_L8N_CC_27 IO_L8N_CC_29 BA37 J27 IO_L8N_CC_5 IO_L8N_CC_6 AR27 G22 IO_L8N_CC_7 IO_L8N_CC_8 AR24 SXM_ADC_CNV C36 IO_L9P_CC_27 IO_L9P_CC_29 AY37 J18 IO_L9P_CC_5 IO_L9P_CC_6 AN20 G21 IO_L9P_CC_7 IO_L9P_CC_8 AU21 SXM_DAC_MOSI C35 IO_L9N_CC_27 IO_L9N_CC_29 AW36 H18 IO_L9N_CC_5 IO_L9N_CC_6 AN19 F21 IO_L9N_CC_7 IO_L9N_CC_8 AT21 SXM_DAC_SPCK A37 BB36 K18 AN18 E22 AV21 IO_L10P_CC_27 IO_L10P_CC_29 IO_L10P_CC_5 IO_L10P_CC_6 IO_L10P_CC_7 IO_L10P_CC_8 SXM_DAC_SYNC_N A36 BA36 K19 AM18 E23 AV20 GND IO_L10N_CC_27 IO_L10N_CC_29 IO_L10N_CC_5 IO_L10N_CC_6 IO_L10N_CC_7 IO_L10N_CC_8 SXM_TEC_PWM B37 IO_L11P_CC_27 IO_L11P_CC_29 AY35 K27 IO_L11P_CC_5 IO_L11P_CC_6 AN26 F24 IO_L11P_CC_7 IO_L11P_CC_8 AU24 SXM_CW_PWM B36 IO_L11N_CC_27 IO_L11N_CC_29 AW35 L26 IO_L11N_CC_5 IO_L11N_CC_6 AP26 G23 IO_L11N_CC_7 IO_L11N_CC_8 AV25 ZLE C38 IO_L12P_VRN_27 IO_L12P_VRN_29 BB34 N20 IO_L12P_VRN_5 IO_L12P_VRN_6 AR18 E19 IO_L12P_VRN_7 IO_L12P_VRN_8 AU23 4.7K FLASH_RESET_N D38 IO_L12N_VRP_27 IO_L12N_VRP_29 BA35 P20 IO_L12N_VRP_5 IO_L12N_VRP_6 AP18 D18 IO_L12N_VRP_7 IO_L12N_VRP_8 AU22 SXM_ADC_MOSI C39 BB33 G27 AN25 J23 AV23 R75 IO_L13P_27 IO_L13P_29 IO_L13P_5 IO_L13P_6 IO_L13P_7 IO_L13P_8 V5_FRANG_ON C40 IO_L13N_27 IO_L13N_29 BA34 F27 IO_L13N_5 IO_L13N_6 AP25 H23 IO_L13N_7 IO_L13N_8 AV24 SXM_TEC_ENABLE B39 IO_L14P_27 IO_L14P_29 AY33 M19 IO_L14P_5 IO_L14P_6 AT19 E20 IO_L14P_7 IO_L14P_8 AR23 B38 IO_L14N_VREF_27 IO_L14N_VREF_29 AY34 N19 IO_L14N_VREF_5 IO_L14N_VREF_6 AR19 F20 IO_L14N_VREF_7 IO_L14N_VREF_8 AP22 RADCOVER_LIMITSWITCH A39 IO_L15P_27 IO_L15P_29 AW33 G28 IO_L15P_5 IO_L15P_6 AM24 G24 IO_L15P_7 IO_L15P_8 AR22 V5_FRANG_ON_2 A40 IO_L15N_27 IO_L15N_29 AW32 H28 IO_L15N_5 IO_L15N_6 AN24 H24 IO_L15N_7 IO_L15N_8 AT22 R219 4.7K A41 IO_L16P_27 IO_L16P_29 AY32 M18 IO_L16P_5 IO_L16P_6 AK18 F19 IO_L16P_7 IO_L16P_8 AM22 LLD B41 IO_L16N_27 IO_L16N_29 BA32 N18 IO_L16N_5 IO_L16N_6 AK19 G19 IO_L16N_7 IO_L16N_8 AM23 R214 4.7K B42 IO_L17P_27 IO_L17P_29 BB32 G29 IO_L17P_5 IO_L17P_6 AK24 F26 IO_L17P_7 IO_L17P_8 AN23 CLINK_RESET_N C41 IO_L17N_27 IO_L17N_29 BB31 F29 IO_L17N_5 IO_L17N_6 AK25 F25 IO_L17N_7 IO_L17N_8 AP23 SXM_DAC_SYNC_N2 D40 IO_L18P_27 IO_L18P_29 BA30 L20 IO_L18P_5 IO_L18P_6 AM19 H19 IO_L18P_7 IO_L18P_8 AP20 R209 4.7K D41 IO_L18N_27 IO_L18N_29 BA31 L19 IO_L18N_5 IO_L18N_6 AL19 H20 IO_L18N_7 IO_L18N_8 AP21 R218 4.7K E42 IO_L19P_27 IO_L19P_29 AY30 H29 IO_L19P_5 IO_L19P_6 AL25 H25 IO_L19P_7 IO_L19P_8 AN21 R222 4.7K D42 IO_L19N_27 IO_L19N_29 AW31 H30 IO_L19N_5 IO_L19N_6 AL24 G26 IO_L19N_7 IO_L19N_8 AM21

GND XQ5VFX130T-1EF1738I XQ5VFX130T-1EF1738I XQ5VFX130T-1EF1738I

J72 1 SQ50TP GND GND GND GND GND GND J73 1 SQ50TP

J74 1 SQ50TP

J75 1 SQ50TP J88 1 SQ50TP J89 1 SQ50TP

98 VIRTEX-5 MGT I/O AND GND BANKS

U22

K21 U29 GND174 GND261 U22 R21 GND175 GND262 W29 U21 AA29 GND176 GND263 F2 AE13 W21 AC29 GND GND87 GND177 GND264 G2 AG13 AE21 AE29 GND1 GND88 GND178 GND265 M2 AJ13 AG21 AJ29 GND2 GND89 GND179 GND266 N2 AL13 AK21 AP29 GND3 GND90 GND180 GND267 V2 D14 AR21 AW29 GND4 GND91 GND181 GND268 W2 P14 H22 B30 GND5 GND92 GND182 GND269 AD2 V14 P22 M30 GND6 GND93 GND183 GND270 AE2 Y14 T22 V30 GND7 GND94 GND184 GND271 AK2 AB14 V22 Y30 GND8 GND95 GND185 GND272 AL2 AD14 AD22 AB30 GND9 GND96 GND186 GND273 AT2 AF14 AF22 AD30 GND10 GND97 GND187 GND274 AU2 AJ14 AH22 AM30 GND11 GND98 GND188 GND275 B3 AP14 AN22 BB30 GND12 GND99 GND189 GND276 BA3 AW14 AV22 E31 GND13 GND100 GND190 GND277 B4 B15 A23 K31 GND14 GND101 GND191 GND278 E4 G15 L23 R31 GND15 GND102 GND192 GND279 H4 M15 R23 W31 GND16 GND103 GND193 GND280 J4 U15 U23 AA31 GND17 GND104 GND194 GND281 L4 W15 W23 AC31 GND18 GND105 GND195 GND282 P4 AA15 AA23 AE31 GND19 GND106 GND196 GND283 U4 AC15 AC23 AK31 GND20 GND107 GND197 GND284 Y4 AE15 AE23 AR31 GND21 GND108 GND198 GND285 AC4 AG15 AG23 H32 GND22 GND109 GND199 GND286 AF4 AM15 AJ23 N32 GND23 GND110 GND200 GND287 AJ4 AU15 AL23 V32 GND24 GND111 GND201 GND288 AM4 BA15 BA23 AC32 GND25 GND112 GND202 GND289 AP4 B16 D24 AH32 GND26 GND113 GND203 GND290 AR4 E16 J24 AN32 GND27 GND114 GND204 GND291 AV4 K16 P24 AV32 GND28 GND115 GND205 GND292 BA4 P16 T24 A33 GND29 GND116 GND206 GND293 G5 T16 V24 L33 GND30 GND117 GND207 GND294 M5 V16 Y24 T33 GND31 GND118 GND208 GND295 U5 Y16 AB24 AA33 GND32 GND119 GND209 GND296 AB5 AB16 AD24 AF33 GND33 GND120 GND210 GND297 AG5 AD16 AF24 AL33 GND34 GND121 GND211 GND298 AM5 AF16 AH24 BA33 GND35 GND122 GND212 GND299 AU5 AK16 AP24 D34 GND36 GND123 GND213 GND300 D6 BA16 G25 P34 GND37 GND124 GND214 GND301 K6 D17 M25 W34 GND38 GND125 GND215 GND302 Y6 N17 R25 AD34 GND39 GND126 GND216 GND303 AK6 R17 U25 AP34 GND40 GND127 GND217 GND304 AR6 U17 W25 G35 GND41 GND128 GND218 GND305 AW6 W17 AA25 M35 GND42 GND129 GND219 GND306 N7 AA17 AC25 U35 GND43 GND130 GND220 GND307 AC7 AC17 AE25 AG35 GND44 GND131 GND221 GND308 AN7 AE17 AG25 AU35 GND45 GND132 GND222 GND309 D8 AG17 AJ25 BB35 GND46 GND133 GND223 GND310 F8 AJ17 AM25 K36 GND47 GND134 GND224 GND311 T8 AN17 AU25 Y36 GND48 GND135 GND225 GND312 AF8 AW17 BB25 AK36 GND49 GND136 GND226 GND313 AT8 F18 K26 AY36 GND50 GND137 GND227 GND314 AW8 L18 T26 C37 GND51 GND138 GND228 GND315 B9 T18 V26 N37 GND52 GND139 GND229 GND316 J9 V18 Y26 AC37 GND53 GND140 GND230 GND317 W9 Y18 AB26 AN37 GND54 GND141 GND231 GND318 AJ9 AB18 AD26 A38 GND55 GND142 GND232 GND319 BA9 AD18 AF26 F38 GND56 GND143 GND233 GND320 B10 AF18 AH26 T38 GND57 GND144 GND234 GND321 M10 AH18 AK26 AF38 GND58 GND145 GND235 GND322 AB10 AL18 AY26 AT38 GND59 GND146 GND236 GND323 AM10 AT18 C27 BA38 GND60 GND147 GND237 GND324 BA10 A19 N27 J39 GND61 GND148 GND238 GND325 D11 B19 R27 W39 GND62 GND149 GND239 GND326 E11 C19 U27 AJ39 GND63 GND150 GND240 GND327 K11 J19 W27 AW39 GND64 GND151 GND241 GND328 R11 P19 AA27 B40 GND65 GND152 GND242 GND329 Y11 R19 AC27 M40 GND66 GND153 GND243 GND330 AC11 U19 AE27 AB40 GND67 GND154 GND244 GND331 AE11 W19 AG27 AM40 GND68 GND155 GND245 GND332 AR11 AA19 AJ27 BB40 GND69 GND156 GND246 GND333 AW11 AC19 AN27 E41 GND70 GND157 GND247 GND334 H12 AE19 A28 R41 GND71 GND158 GND248 GND335 N12 AG19 F28 AE41 GND72 GND159 GND249 GND336 T12 AJ19 L28 AR41 GND73 GND160 GND250 GND337 V12 AW19 T28 AY41 GND74 GND161 GND251 GND338 Y12 BB19 V28 C42 GND75 GND162 GND252 GND339 AB12 B20 Y28 H42 GND76 GND163 GND253 GND340 AD12 M20 AB28 N42 GND77 GND164 GND254 GND341 AH12 T20 AD28 V42 GND78 GND165 GND255 GND342 AN12 V20 AF28 AC42 GND79 GND166 GND256 GND343 AV12 Y20 AH28 AH42 GND80 GND167 GND257 GND344 L13 AB20 AT28 AN42 GND81 GND168 GND258 GND345 R13 AD20 J29 AV42 GND82 GND169 GND259 GND346 U13 AF20 P29 GND83 GND170 GND260 W13 AH20 GND84 GND171 XQ5VFX130T-1EF1738I AA13 GND85 GND172 AM20 AC13 GND86 GND173 E21

XQ5VFX130T-1EF1738I

GND GND GND GND

99 U22

MGT MGTTXP0_112 T2 U1 MGTRXP0_112 MGTTXN0_112 U2 V1 MGTRXN0_112 MGTTXP1_112 AA2 Y1 MGTRXP1_112 MGTTXN1_112 Y2 W1 MGTRXN1_112 MGTAVTTTX1_112 AA3 VIRTEX-5 VCC +1.0V, +2.5V, +3.3V V4 MGTREFCLKP_112 MGTAVTTTX2_112 T3 V3 MGTREFCLKN_112 MGTAVTTRX_112 U3 AB4 MGTRREF_112 MGTAVCCPLL_112 Y3

MGTAVTTRXC AA5

MGTTXP0_114 AB2 AC1 MGTRXP0_114 MGTTXN0_114 AC2 AD1 MGTRXN0_114 MGTTXP1_114 AG2 AF1 MGTRXP1_114 MGTTXN1_114 AF2 AE1 MGTRXN1_114 MGTAVTTTX1_114 AB3 +1.0V +1.0V +2.5V AD4 MGTREFCLKP_114 MGTAVTTTX2_114 AG3 AD3 MGTREFCLKN_114 MGTAVTTRX_114 AC3 MGTAVCCPLL_114 AF3 +2.5V +3.3V +2.5V +3.3V MGTTXP0_116 K2 L1 MGTRXP0_116 MGTTXN0_116 L2 U22 M1 MGTRXN0_116 MGTTXP1_116 R2 U22 P1 MGTRXP1_116 MGTTXN1_116 P2 N1 MGTRXN1_116 MGTAVTTTX1_116 K3 R12 VCCAUX VCCINT46 U20 AL28 VCCO_0 VCCO_18 AD9 M4 MGTREFCLKP_116 MGTAVTTTX2_116 R3 U12 VCCAUX1 VCCINT47 W20 AG30 VCCO_0 VCCO_18 AG10 M3 MGTREFCLKN_116 MGTAVTTRX_116 L3 W12 VCCAUX2 VCCINT48 AA20 F13 VCCO_1 VCCO_19 L38 MGTAVCCPLL_116 P3 AA12 VCCAUX3 VCCINT49 AC20 J14 VCCO_1 VCCO_19 G40 MGTTXP0_118 AH2 AC12 VCCAUX4 VCCINT50 AE20 AR26 VCCO_2 VCCO_19 K41 AJ1 MGTRXP0_118 MGTTXN0_118 AJ2 AE12 VCCAUX5 VCCINT51 AG20 AV27 VCCO_2 VCCO_20 R6 AK1 MGTRXN0_118 MGTTXP1_118 AN2 AJ12 VCCAUX6 VCCINT52 AJ20 E26 VCCO_3 VCCO_20 L8 AM1 MGTRXP1_118 MGTTXN1_118 AM2 T13 VCCAUX7 VCCINT53 P21 H27 VCCO_3 VCCO_20 P9 AL1 MGTRXN1_118 MGTAVTTTX1_118 AH3 AF13 VCCAUX8 VCCINT54 T21 AT13 VCCO_4 VCCO_21 AJ34 AK4 MGTREFCLKP_118 MGTAVTTTX2_118 AN3 AH13 VCCAUX9 VCCINT55 V21 AR16 VCCO_4 VCCO_21 AM35 AK3 MGTREFCLKN_118 MGTAVTTRX_118 AJ3 T29 VCCAUX10 VCCINT56 AD21 C22 VCCO_5 VCCO_21 AL38 MGTAVCCPLL_118 AM3 AF29 VCCAUX11 VCCINT57 AF21 F23 VCCO_5 VCCO_23 E36 U30 VCCAUX12 VCCINT58 AH21 B25 VCCO_5 VCCO_23 H37 MGTTXP0_120 D2 W30 VCCAUX13 VCCINT59 R22 AY21 VCCO_6 VCCO_23 D39 E1 MGTRXP0_120 MGTTXN0_120 E2 AA30 VCCAUX14 VCCINT60 U22 AT23 VCCO_6 VCCO_24 E6 F1 MGTRXN0_120 MGTTXP1_120 J2 AC30 VCCAUX15 VCCINT61 W22 AW24 VCCO_6 VCCO_24 H7 H1 MGTRXP1_120 MGTTXN1_120 H2 AE30 VCCAUX16 VCCINT62 AE22 H17 VCCO_7 VCCO_24 G10 G1 MGTRXN1_120 MGTAVTTTX1_120 D3 Y31 VCCAUX17 VCCINT63 AG22 D19 VCCO_7 VCCO_25 AR36 F4 MGTREFCLKP_120 MGTAVTTTX2_120 J3 AB31 VCCAUX18 VCCINT64 P23 G20 VCCO_7 VCCO_25 AP39 F3 MGTREFCLKN_120 MGTAVTTRX_120 E3 AD31 VCCAUX19 VCCINT65 T23 AV17 VCCO_8 VCCO_25 AU40 MGTAVCCPLL_120 H3 VCCINT66 V23 AP19 VCCO_8 VCCO_26 AH7 V13 VCCINT MGTTXP0_122 AP2 VCCINT67 Y23 AU20 VCCO_8 VCCO_26 AL8 Y13 VCCINT1 AR1 MGTRXP0_122 MGTTXN0_122 AR2 VCCINT68 AB23 V37 VCCO_11 VCCO_26 AK11 AB13 VCCINT2 AT1 MGTRXN0_122 MGTTXP1_122 AW2 VCCINT69 AD23 AA38 VCCO_11 VCCO_27 F33 AD13 VCCINT3 AV1 MGTRXP1_122 MGTTXN1_122 AV2 VCCINT70 AF23 Y41 VCCO_11 VCCO_27 J34 U14 VCCINT4 AU1 MGTRXN1_122 MGTAVTTTX1_122 AP3 VCCINT71 AH23 V7 VCCO_12 VCCO_27 B35 W14 VCCINT5 AT4 MGTREFCLKP_122 MGTAVTTTX2_122 AW3 VCCINT72 R24 AA8 VCCO_12 VCCO_29 AT33 AA14 VCCINT6 AT3 MGTREFCLKN_122 MGTAVTTRX_122 AR3 VCCINT73 U24 U10 VCCO_12 VCCO_29 AW34 AC14 VCCINT7 MGTAVCCPLL_122 AV3 VCCINT74 W24 AB35 VCCO_13 VCCO_29 AV37 AE14 VCCINT8 VCCINT75 AA24 AE36 VCCO_13 VCCO_31 D29 MGTTXP0_124 B6 AG14 VCCINT9 VCCINT76 AC24 AD39 VCCO_13 VCCO_31 G30 A5 MGTRXP0_124 MGTTXN0_124 B5 T15 VCCINT10 VCCINT77 AE24 R36 VCCO_15 VCCO_31 C32 A4 MGTRXN0_124 MGTTXP1_124 B1 V15 VCCINT11 VCCINT78 AG24 P39 VCCO_15 VCCO_33 BA28 A2 MGTRXP1_124 MGTTXN1_124 B2 Y15 VCCINT12 VCCINT79 AJ24 U40 VCCO_15 VCCO_33 AU30 A3 MGTRXN1_124 MGTAVTTTX1_124 C1 AB15 VCCINT13 VCCINT80 T25 AH37 VCCO_17 VCCO_33 AY31 C4 MGTREFCLKP_124 MGTAVTTTX2_124 C6 AD15 VCCINT14 VCCINT81 V25 AG40 VCCO_17 VCCO_34 AV7 C3 MGTREFCLKN_124 MGTAVTTRX_124 C5 AF15 VCCINT15 VCCINT82 Y25 AK41 VCCO_17 VCCO_34 AP9 MGTAVCCPLL_124 C2 R16 VCCINT16 VCCINT83 AB25 AE6 VCCO_18 VCCO_34 AU10 U16 VCCINT17 MGTTXP0_126 BA1 VCCINT84 AD25 W16 VCCINT18 BB2 MGTRXP0_126 MGTTXN0_126 BA2 VCCINT85 AF25 AA16 VCCINT19 XQ5VFX130T-1EF1738I BB3 MGTRXN0_126 MGTTXP1_126 BA6 VCCINT86 AH25 AC16 VCCINT20 BB5 MGTRXP1_126 MGTTXN1_126 BA5 VCCINT87 R26 AE16 VCCINT21 BB4 MGTRXN1_126 MGTAVTTTX1_126 AY1 VCCINT88 U26 AG16 VCCINT22 AW4 MGTREFCLKP_126 MGTAVTTTX2_126 AY6 VCCINT89 W26 T17 VCCINT23 AY4 MGTREFCLKN_126 MGTAVTTRX_126 AY2 VCCINT90 AA26 V17 VCCINT24 MGTAVCCPLL_126 AY5 VCCINT91 AC26 GND Y17 VCCINT25 VCCINT92 AE26 MGTTXP0_128 B12 AB17 VCCINT26 VCCINT93 AG26 A11 MGTRXP0_128 MGTTXN0_128 B11 AD17 VCCINT27 +1.0V +1.0V VCCINT94 T27 A10 MGTRXN0_128 MGTTXP1_128 B7 AF17 VCCINT28 VCCINT95 V27 A8 MGTRXP1_128 MGTTXN1_128 B8 AH17 VCCINT29 VCCINT96 Y27 A9 MGTRXN1_128 MGTAVTTTX1_128 C12 R18 VCCINT30 VCCINT97 AB27 D10 MGTREFCLKP_128 MGTAVTTTX2_128 C7 U18 VCCINT31 VCCINT98 AD27 C10 MGTREFCLKN_128 MGTAVTTRX_128 C11 W18 VCCINT32 VCCINT99 AF27 MGTAVCCPLL_128 C8 AA18 VCCINT33 VCCINT100 AH27 AC18 VCCINT34 U22 MGTTXP0_130 BA7 VCCINT101 R28 AE18 VCCINT35 BB8 MGTRXP0_130 MGTTXN0_130 BA8 VCCINT102 U28 MGTAVCC_124 D4 AG18 VCCINT36 W3 MGTAVCC_112 BB9 MGTRXN0_130 MGTTXP1_130 BA12 VCCINT103 W28 MGTAVCC_124 D5 AJ18 VCCINT37 W4 MGTAVCC_112 BB11 MGTRXP1_130 MGTTXN1_130 BA11 VCCINT104 AA28 MGTAVCC_126 AW5 T19 VCCINT38 AE3 MGTAVCC_114 BB10 MGTRXN1_130 MGTAVTTTX1_130 AY12 VCCINT105 AC28 MGTAVCC_126 AY3 V19 VCCINT39 AE4 MGTAVCC_114 AW9 MGTREFCLKP_130 MGTAVTTTX2_130 AY7 VCCINT106 AE28 MGTAVCC_128 C9 Y19 VCCINT40 N3 MGTAVCC_116 AY9 MGTREFCLKN_130 MGTAVTTRX_130 AY8 VCCINT107 AG28 MGTAVCC_128 D9 AB19 VCCINT41 N4 MGTAVCC_116 MGTAVCCPLL_130 AY11 VCCINT108 V29 MGTAVCC_130 AW10 AD19 VCCINT42 AL3 MGTAVCC_118 VCCINT109 Y29 MGTAVCC_130 AY10 NC_135 B18 AF19 VCCINT43 AL4 MGTAVCC_118 VCCINT110 AB29 NC_151 C15 A17 NC_121 NC_136 B17 AH19 VCCINT44 G3 MGTAVCC_120 VCCINT111 AD29 NC_152 D15 A16 NC_122 NC_137 B13 R20 VCCINT45 G4 MGTAVCC_120 NC_153 AW16 A14 NC_123 NC_138 B14 AU3 MGTAVCC_122 XQ5VFX130T-1EF1738I NC_154 AY16 A15 NC_124 NC_139 C13 AU4 MGTAVCC_122 D16 NC_125 NC_140 C18 XQ5VFX130T-1EF1738I C16 NC_126 NC_141 C17 NC_142 C14 GND NC_143 BA13 BB14 NC_127 NC_144 BA14 BB15 BA18 NC_128 NC_145 BB17 BA17 GND NC_129 NC_146 BB16 NC_130 NC_147 AY13 AW15 NC_131 NC_148 AY18 AY15 AY14 NC_132 NC_149 NC_150 AY17 AA4 NC_133 GND Y5 NC_134 XQ5VFX130T-1EF1738I

100 VIRTEX-5 DECOUPLING

+2.5V

+ C58 + C59 + C60 33uF 33uF 33uF GND

GND

+1.0V

+ C119 + C122 + C123 330uF 330uF 330uF

GND

101 102 Appendix B

Simulation Code

The following Appendix contains python code developed for SXM data analysis.

B.1 SXM Simulated Instrument Response Code

The following section contains SXM simulated response code used to attempt to fit SXM flight data to Chianti solar abundance models. This code implements SXM Data Pipeline code written by the REXIS Science Team.

#!/usr/bin/env python3 # −*− coding : utf −8 −*− """ Created on Fri Jun 28 09:26:40 2019

@author: andrewcummings """

import ChiantiPy.core as ch import ChiantiPy.tools.filters as cf import matplotlib.pyplot as plt import numpy as np

103 #temp1 = np.arange(1.e+6,625e+4,25.e+4) #temp2 = np.arange(65.e+5,10.e+6,5.e+5) #temp3 = np.arange(10.e+6,21.e+6,1.e+6) #temp12 = np. concatenate((temp1,temp2),axis=None) #T = np.concatenate((temp12,temp3), axis=None)

"""file name""" def chianti_spectra_generation(file ,abundance): file =’sun_photospheric_1998_grevesse_highres.npz’ #abundances : # sun_photospheric_1998_grevesse , sun_photospheric_2015_scott_ext , sun_coronal_feldman_1992_ext , sun_coronal_2012_schmelz_ext

E= np.arange(0.0495, 25.0005, 0.005) T=np.array([ 0.5, 0.6, 0.7, 0.8, 0.9, 1. , 1.1, 1.2, 1.3, 1.4, 1.5, 1.6, 1.7, 1.8, 1.9, 2. , 2.1, 2.2, 2.3, 2.4, 2.5, 2.6, 2.7, 2.8, 2.9, 3. , 3.1, 3.2, 3.3, 3.4, 3.5, 3.6, 3.7, 3.8, 3.9, 4. , 4.1, 4.2, 4.3, 4.4, 4.5, 4.6, 4.7, 4.8, 4.9, 5. , 5.1, 5.2, 5.3, 5.4,

104 5.5, 5.6, 5.7, 5.8, 5.9, 6. , 6.1, 6.2, 6.3, 6.4, 6.5, 6.6, 6.7, 6.8, 6.9, 7. , 7.1, 7.2, 7.3, 7.4, 7.5, 7.6, 7.7, 7.8, 7.9, 8. , 8.1, 8.2, 8.3, 8.4, 8.5, 8.6, 8.7, 8.8, 8.9, 9. , 9.1, 9.2, 9.3, 9.4, 9.5, 9.6, 9.7, 9.8, 9.9, 10. , 10.1, 10.2, 10.3, 10.4, 10.5, 10.6, 10.7, 10.8, 10.9, 11. , 11.1, 11.2, 11.3, 11.4, 11.5, 11.6, 11.7, 11.8, 11.9, 12. , 12.1, 12.2, 12.3, 12.4, 12.5, 12.6, 12.7, 12.8, 12.9, 13. , 13.1, 13.2, 13.3, 13.4, 13.5, 13.6, 13.7, 13.8, 13.9, 14. , 14.1, 14.2, 14.3, 14.4, 14.5, 14.6, 14.7, 14.8, 14.9, 15. , 15.1, 15.2, 15.3, 15.4, 15.5, 15.6, 15.7, 15.8, 15.9, 16. , 16.1, 16.2, 16.3, 16.4, 16.5, 16.6, 16.7, 16.8, 16.9, 17. , 17.1, 17.2, 17.3, 17.4, 17.5, 17.6, 17.7, 17.8, 17.9, 18. , 18.1, 18.2, 18.3, 18.4, 18.5, 18.6, 18.7, 18.8, 18.9,

105 19. , 19.1, 19.2, 19.3, 19.4, 19.5, 19.6, 19.7, 19.8, 1 9 . 9 , 20. ] )

T=T*1. e6

#T= np.logspace(5, 7, 50) s= ch.spectrum(T, wavelength= 12.4/E, eDensity= 1e9, em= 1e27, filter= (cf.gaussianR, 10000), abundance=’sun_photospheric_1998_grevesse ’ , minAbund= 1e −6,verbose=1)

I= s.Spectrum #plt.plot(E, I[’intensity ’][1]) #plt.xlabel(’Energy [keV] ’) #plt.ylabel(I[’ylabel ’][: − 2 ] ) np.savez_compressed( file , I ,E=E,T=T, wavelength = 12.4/E) f = np.load(file) s= dict(f[’arr_0’]. tolist()) wvl = s[’wavelength ’] T=f [ ’T ’ ] T=T/1. e6 E = 12.4/ wvl intensity= s[’intensity ’] for i in range(len(T)):

106 intensity[i ,:] = intensity[i,:] * 4 . 0 6 * 1 . e6 *( wvl )**3 data = intensity np.savez_compressed(file , E=E, data=data .T,T=T)

B.2 SXM Histogram Rebinning

Code used to rebin Orbital B and Orbital R flight data to attempt to recover x-ray signal. SXM flight data was loaded manually into the rebinner because of x-raycount rate differences that existed between the two sections of Orbital R. Level 0 SXMflight data is delineated by "YYYYDDD," where DDD is the day of the year that data was recorded.

import h5py as h import math as m import numpy as np

’2019182_L0.h5’,’2019183_L0.h5’,’2019184_L0.h5’ , ’2019185_L0.h5’,’2019186_L0.h5’ , ’2019187_L0.h5’,’2019188_L0.h5’,’2019189_L0.h5’ , ’2019190_L0.h5’,’2019191_L0.h5’ , ’2019192_L0.h5’,’2019193_L0.h5’,’2019194_L0.h5’ , ’2019195_L0.h5’,’2019196_L0.h5 ’] file=[ ’2019197_L0.h5’,’2019198_L0.h5’,’2019199_L0.h5’ , ’2019200_L0.h5’,’2019201_L0.h5’ , ’2019202_L0.h5’,’2019203_L0.h5’ , ’2019204_L0.h5’,’2019205_L0.h5’,’2019206_L0.h5’ , ’2019207_L0.h5’,’2019208_L0.h5’ ,

107 ’2019209_L0.h5’,’2019210_L0.h5’,’2019211_L0.h5’ , ’2019212_L0.h5’,’2019213_L0.h5’ , ’2019214_L0.h5’,’2019215_L0.h5’,’2019216_L0.h5’ , ’2019217_L0.h5’,’2019218_L0.h5 ’]

#dtype([( ’sxm_period’, ’

def concatenate_hdr(ENTRY): f000 = h.File(file[0],’r’) b000 = f000 [ ’data/tlm_sxm_data/hdr ’][ENTRY] for i in range(1,18): # NEED TO CHANGE THIS TO range(1,len(file )) [this currently throws an error for 18th or 19th entry in file] f_now = h.File(file[i],’r’) b_now = f_now[ ’ data/tlm_sxm_data/hdr ’ ] [ENTRY] i f i == 1 : c_now = np . concatenate ( ( b000 , b_now) , 0 ) current = c_now e l s e : c_now = np . concatenate ( ( current , b_now) , 0 ) current = c_now return current

108 def concatenate_prehdr(ENTRY): f000 = h.File(file[0],’r’) b000 = f000 [ ’data/tlm_sxm_data/pre_hdr ’][ENTRY] for i in range(1,18): # NEED TO CHANGE THIS TO range(1,len(file )) [this currently throws an error for 18th or 19th entry in file] f_now = h.File(file[i],’r’) b_now = f_now[ ’ data/tlm_sxm_data/pre_hdr ’ ] [ENTRY] i f i == 1 : c_now = np . concatenate ( ( b000 , b_now) , 0 ) current = c_now e l s e : c_now = np . concatenate ( ( current , b_now) , 0 ) current = c_now return current s = concatenate_prehdr(’SpacecraftTime ’) def binner(data,bins): while len(data) > bins: #if len(data)%2==0: data2 = ([(a+b)/2 for a,b in zip(data[::2] , data[1::2])]) data = np.asarray(data2) #print(data) return data def create_data_prehdr(width): sync_data = concatenate_prehdr(’Sync’) #BINNED_bin_data = binner(sync_data , width) −>

109 #binner function doesn’t work with binary data length_data = concatenate_prehdr(’Length ’) BINNED_length_data = binner(length_data ,width)

PacketID_data = concatenate_prehdr(’PacketID ’) BINNED_PacketID_data = binner(PacketID_data , width)

GlobalCount_data = concatenate_prehdr(’GlobalCount ’) BINNED_GlobalCount_data = binner(GlobalCount_data , width)

Time_secs_data = concatenate_prehdr(’Time(secs ) ’) BINNED_Time_secs_data = binner(Time_secs_data , width)

Time_subsecs_data = concatenate_prehdr(’Time(subsecs) ’) BINNED_Time_subsecs_data = binner(Time_subsecs_data , width)

LocalCount_data = concatenate_prehdr(’LocalCount ’) BINNED_LocalCount_data = binner(LocalCount_data , width)

LocalTotal_data = concatenate_prehdr(’LocalTotal ’) BINNED_LocalTotal_data = binner(LocalTotal_data ,width)

SpacecraftTime_data = concatenate_prehdr(’SpacecraftTime ’) BINNED_SpacecraftTime_data = binner(SpacecraftTime_data ,width) dtp = np.dtype([ #(’Sync’ , ’S30’ ), (’Length’ ,’

110 (’GlobalCount’ , ’

bpdata= np.rec.fromarrays([ #sync_data , #SHOULD BE BINNED DATA but # there’s a bug currently (binner function not #compatible with binary files) BINNED_length_data , BINNED_PacketID_data , BINNED_GlobalCount_data , BINNED_Time_secs_data , BINNED_Time_subsecs_data , BINNED_LocalCount_data , BINNED_LocalTotal_data , BINNED_SpacecraftTime_data] , dtype= dtp)

return bpdata create_data_prehdr(1) def create_data_hdr(width): ’’’ hard coding this since for now ’’’ bin_data = concatenate_hdr(’bin ’) BINNED_bin_data = binner(bin_data ,width)

111 sxm_period_data = concatenate_hdr(’sxm_period ’) BINNED_sxm_period_data = binner(sxm_period_data , width)

TotalEventsCnt_data = concatenate_hdr(’TotalEventsCnt ’) BINNED_TotalEventsCnt_data = binner(TotalEventsCnt_data , width ) underflowEventCnt_data = concatenate_hdr(’underflowEventCnt ’) BINNED_underflowEventCnt_data = binner(underflowEventCnt_data , width ) overflowEventCnt_data = concatenate_hdr(’overflowEventCnt ’) BINNED_overflowEventCnt_data = binner(overflowEventCnt_data , width ) scTime_subsecs_data = concatenate_hdr(’scTime(subsecs) ’) BINNED_scTime_subsecs_data = binner(scTime_subsecs_data , width ) scTime_secs_data = concatenate_hdr(’scTime(secs ) ’) BINNED_scTime_secs_data = binner(scTime_secs_data , width ) scGlobalCount_data = concatenate_hdr(’scGlobalCount ’) BINNED_scGlobalCount_data = binner(scGlobalCount_data , width ) dt = np.dtype([ (’sxm_period’ , ’

112 (’underflowEventCnt’ , ’

bdata= np.rec.fromarrays([ BINNED_sxm_period_data , BINNED_TotalEventsCnt_data , BINNED_underflowEventCnt_data , BINNED_overflowEventCnt_data , BINNED_bin_data , BINNED_scTime_subsecs_data , BINNED_scTime_secs_data , BINNED_scGlobalCount_data] , dtype= dt)

return bdata def create_file(width,filename): bdata = create_data_hdr(width) bpdata = create_data_prehdr(width) with h.File(filename, ’w’) as f: grp = f.create_group("data") subgrp = grp.create_group("tlm_sxm_data") sub2 = subgrp.create_dataset("hdr",data=bdata) sub3=subgrp. create_dataset("pre_hdr",data=bpdata) f . c l o s e ( ) return

113 create_file(500,’rebinned_data.h5’)

B.3 LTSpice Simulation Readout

This code is used to analyze LTSpice simulation data. LTSpice software was updated between the time early LTspice readout code written by Dr. Branden Allen, and the SXM low count rate root cause investigation. The code was updated to take .txt files instead of .raw files, which was the old LTSpice file output.

#!/usr/bin/env python #−*−encoding=utf −8−*− ’’’ A library for loading the output spice simulations

Author: Branden Allen Date: 2015.06.18 Edited: Andrew Cummings Date: 2019.01.30 ’’’ from __future__ import print_function

#Numerical import numpy as np

#Standard import s t r u c t import re

#####################################################################

114 def open_spice(filename , dtype= ’f ’): with open(filename, ’rb’) as f: d= f . read ( ) div= re.search(’Binary: ’.encode(), d) data= d[div.end()+1:] hdr= d[: div.end()+1]

#Extract the data size= [re.search(i.encode(), hdr).span() for i in [ ’No.␣Points:\s+\d+’ , ’No.␣Variables:\s+\d+’ ]] nrow, ncol= [ int (hdr[i[0]:i [1]]. split(’:’.encode())[ − 1 ] ) for i in s i z e ] #print(nrow,ncol) d= np.reshape(struct .unpack(nrow* ncol *dtype , bytearray ( 5 9 5 2 ) ) , (nrow, ncol)) #[ 1 : ]

#Retrieve the data keys start= re.search(’\nVariables: ’, hdr.decode()).end()+1 end= re.search(’\nBinary: ’, hdr.decode()). start() keys= [i.split() for i in hdr[start:end].decode(). split(’\n’)]

#Generate record array d= np.rec.fromrecords(d, names= [i[1] for i in keys ] ) return d

# Andrew’s Version for txt files def open_text(filename ): with open(filename, "r") as readfile: x =[]

115 y =[]

for l i n e in r e a d f i l e : Type = line.split("\t") x.append(Type[0]) y.append(Type[1]) xlabel = x[0] ylabel = y[0] x . pop (0) y . pop (0) time = np.array(x,dtype=np.float32) time = time *1. e6 value = np.array(y,dtype=np.float32) print (xlabel ,ylabel) return time , value

#####################################################################

116