The Proper Usage Method of Conductive Polymer Solid Aluminum Electrolytic Capacitor
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Momentary Podl Connector and Cable Shorts
Momentary PoDL Connector and Cable Shorts Andy Gardner – Linear Technology Corporation 2 Presentation Objectives • To put forward a momentary connector or cable short fault scenario for Ethernet PoDL. • To quantify the requirements for surviving the energy dissipation and cable voltage transients subsequent to the momentary short. 3 PoDL Circuit with Momentary Short • IPSE= IPD= IL1= IL2= IL3= IL4 at steady-state. • D1-D4 and D5-D8 represent the master and slave PHY body diodes, respectively. • PoDL fuse or circuit breaker will open during a sustained over- current (OC) fault but may not open during a momentary OC fault. 4 PoDL Inductor Current Imbalance during a Cable or Connector Short • During a connector or cable short, the PoDL inductor currents will become unbalanced. • The current in inductors L1 and L2 will increase, while the current in inductors L3 and L4 will reverse. • Maximum inductor energy is limited by the PoDL inductors’ saturation current, i.e. ISAT > IPD(max). • Stored inductor energy resulting from the current imbalance will be dissipated by termination and parasitic resistances as well as the PHYs’ body diodes. • DC blocking capacitors C1-C4 need to be rated for peak transient voltages subsequent to the momentary short. 5 Max Energy Storage in PoDL Coupling Inductors during a Momentary Short • PoDL inductors L1-L4 are constrained by tdroop: −50 × 푡푑푟표표푝 퐿 > 푃표퐷퐿 ln 1 − 0.45 1 퐸 ≈ 4 × × 퐿 × 퐼 2 퐿(푡표푡푎푙) 2 푃표퐷퐿 푆퐴푇 • Example: if tdroop=500ns, LPoDL=42H which yields: ISAT Total EL 1A 84J 3A 756J 10A 8.4mJ 6 Peak Transient Voltage after a Short • The maximum voltage across the PHY DC blocking capacitors C1-C4 following a momentary short assuming damping ratio 휁 is: 퐿푃표퐷퐿 50Ω 푉푚푎푥 ≈ 퐼푠푎푡 × = 퐼푠푎푡 × 퐶휑푏푙표푐푘 2 × 휁 4 × 푡푑푟표표푝 where 퐶 ≥ −휁2 × 휑푏푙표푐푘 50Ω × ln (1 − 0.45) • The maximum voltage differential between the conductors in the twisted pair is then: Vmax(diff) = 2 Vmax ISAT 50/휁 • Example: A critically damped PoDL network (휁=1) with inductor ISAT = 1A yields Vmax(diff) 50V while an inductor ISAT = 10A will yield Vmax(diff) 500V. -
Introduction What Is a Polymer Capacitor?
ECAS series (polymer-type aluminum electrolytic capacitor) No. C2T2CPS-063 Introduction If you take a look at the main board of an electronic device such as a personal computer, you’re likely to see some of the six types of capacitors shown below (Fig. 1). Common types of capacitors include tantalum electrolytic capacitors (MnO2 type and polymer type), aluminum electrolytic capacitors (electrolyte can type, polymer can type, and chip type), and MLCC. Figure 1. Main Types of Capacitors What Is a Polymer Capacitor? There are many other types of capacitors, such as film capacitors and niobium capacitors, but here we will describe polymer capacitors, a type of capacitor produced by Murata among others. In both tantalum electrolytic capacitors and aluminum electrolytic capacitors, a polymer capacitor is a type of electrolytic capacitor in which a conductive polymer is used as the cathode. In a polymer-type aluminum electrolytic capacitor, the anode is made of aluminum foil and the cathode is made of a conductive polymer. In a polymer-type tantalum electrolytic capacitor, the anode is made of the metal tantalum and the cathode is made of a conductive polymer. Figure 2 shows an example of this structure. Figure 2. Example of Structure of Conductive Polymer Aluminum Capacitor In conventional electrolytic capacitors, an electrolyte (electrolytic solution) or manganese dioxide (MnO2) was used as the cathode. Using a conductive polymer instead provides many advantages, making it possible to achieve a lower equivalent series resistance (ESR), more stable thermal characteristics, improved safety, and longer service life. As can be seen in Fig. 1, polymer capacitors have lower ESR than conventional electrolytic Copyright © muRata Manufacturing Co., Ltd. -
Capacitors and Inductors
DC Principles Study Unit Capacitors and Inductors By Robert Cecci In this text, you’ll learn about how capacitors and inductors operate in DC circuits. As an industrial electrician or elec- tronics technician, you’ll be likely to encounter capacitors and inductors in your everyday work. Capacitors and induc- tors are used in many types of industrial power supplies, Preview Preview motor drive systems, and on most industrial electronics printed circuit boards. When you complete this study unit, you’ll be able to • Explain how a capacitor holds a charge • Describe common types of capacitors • Identify capacitor ratings • Calculate the total capacitance of a circuit containing capacitors connected in series or in parallel • Calculate the time constant of a resistance-capacitance (RC) circuit • Explain how inductors are constructed and describe their rating system • Describe how an inductor can regulate the flow of cur- rent in a DC circuit • Calculate the total inductance of a circuit containing inductors connected in series or parallel • Calculate the time constant of a resistance-inductance (RL) circuit Electronics Workbench is a registered trademark, property of Interactive Image Technologies Ltd. and used with permission. You’ll see the symbol shown above at several locations throughout this study unit. This symbol is the logo of Electronics Workbench, a computer-simulated electronics laboratory. The appearance of this symbol in the text mar- gin signals that there’s an Electronics Workbench lab experiment associated with that section of the text. If your program includes Elec tronics Workbench as a part of your iii learning experience, you’ll receive an experiment lab book that describes your Electronics Workbench assignments. -
Short Circuit and Overload Protection Devices Within an Electrical System
TM Information Sheet # 07 Short Circuit and Overload Protection Your Reliable Guide for Power Solutions Devices Within an Electrical System 1.0 Introduction The designer of an electrical system has the responsibility to meet code requirements and to ensure that the equipment and conductors within a system are protected against current flows that will produce destructive temperatures above specified rating and design limits. This information sheet discusses protective devices that are used within a system, how they work and where they are used. 2.0 Overcurrent protection devices: Protection against temperature is termed “overcurrent protection.” Overcurrents are caused by equipment overloads, by short circuits or by ground faults. An overload occurs when equipment is subjected to current above its rated capacity and excessive heat is produced. A short circuit occurs when there is a direct but unintended connection between line-to-line or line-to-neutral conductors. Short circuits can generate temperatures thousands of degrees above designated ratings. A ground fault occurs when electrical current flows from a conductor to uninsulated metal that is not designed to conduct electricity. These uninsulated currents can be lethal. The designer has many overcurrent protection devices to choose from. The two most common are fuses and circuit breakers. Many circuit breakers are also known as molded case breakers or MCBs. Fuses: A fuse is the simplest form of overcurrent protective device but it can be used only once before it must be replaced. A fuse consists of a conducting element enclosed in a glass, ceramic or other non-conductive tube and connected by ferrules at each end of the tube. -
Basic PCB Material Electrical and Thermal Properties for Design Introduction
1 Basic PCB material electrical and thermal properties for design Introduction: In order to design PCBs intelligently it becomes important to understand, among other things, the electrical properties of the board material. This brief paper is an attempt to outline these key properties and offer some descriptions of these parameters. Parameters: The basic ( and almost indispensable) parameters for PCB materials are listed below and further described in the treatment that follows. dk, laminate dielectric constant df, dissipation factor Dielectric loss Conductor loss Thermal effects Frequency performance dk: Use the design dk value which is assumed to be more pertinent to design. Determines such things as impedances and the physical dimensions of microstrip circuits. A reasonable accurate practical formula for the effective dielectric constant derived from the dielectric constant of the material is: -1/2 εeff = [ ( εr +1)/2] + [ ( εr -1)/2][1+ (12.h/W)] Here h = thickness of PCB material W = width of the trace εeff = effective dielectric constant εr = dielectric constant of pcb material df: The dissipation factor (df) is a measure of loss-rate of energy of a mode of oscillation in a dissipative system. It is the reciprocal of quality factor Q, which represents the Signal Processing Group Inc., technical memorandum. Website: http://www.signalpro.biz. Signal Processing Gtroup Inc., designs, develops and manufactures analog and wireless ASICs and modules using state of the art semiconductor, PCB and packaging technologies. For a free no obligation quote on your product please send your requirements to us via email at [email protected] or through the Contact item on the website. -
Uprating of Electrolytic Capacitors
White Paper Uprating of Electrolytic Capacitors By Joelle Arnold Uprating of Electrolytic Capacitors Aluminum electrolytic capacitors are comprised of two aluminum foils, a cathode and an anode, rolled together with an electrolyte-soaked paper spacer in between. An oxide film is grown on the anode to create the dielectric. Aluminum electrolytic capacitors are primarily used to filter low-frequency electrical signals, primarily in power designs. The critical functional parameters for aluminum electrolytic capacitors are defined as capacitance (C), leakage current (LC), equivalent series resistance (ESR), impedance (Z), and dissipation factor (DF). These five parameters are interrelated through the following schematic. Physically, leakage current (LC) tends to be primarily driven by the behavior of the dielectric. ESR is primarily driven by the behavior of the electrolyte. Physically, impedance (Z) is a summation of all the resistances throughout the capacitor, including resistances due to packaging. Electrically, Z is the summation of ESR and either the capacitive reactance (XC), at low frequency, or the inductance (LESL), at high frequency (see Figure 1). Dissipation factor is the ratio of ESR over XC. Therefore, a low ESR tends to give a low impedance and a low dissipation factor. 1.1 Functional Parameters (Specified in Datasheet) The functional parameters that can be provided in manufacturers’ datasheets are listed below 1.1.1 Capacitance vs. Temperature It can be seen that the manufacturer’s guarantee of ±20% stability of the capacitance is only relevant at room temperature. While a source of potential concern when operating aluminum electrolytic capacitors over an extended temperature range, previous research has demonstrated that the capacitance of this capacitor is extremely stable as a function of temperature (see Figure 2 and Figure 4). -
Equivalent Series Resistance (ESR) of Capacitors
Application Note 1 of 5 Equivalent Series Resistance (ESR) of Capacitors Questions continually arise concerning the correct definition of the ESR (Equivalent Series Resistance) of a capacitor and, more particularly, the difference between ESR and the actual physical series resistance (which we'll call Ras), the ohmic resistance of the leads and plates or foils. The definition and application of the term ESR has often been misconstrued. We hope this note will answer any questions and clarify any confusion that might exist. Very briefly, ESR is a measure of the total lossiness of a capacitor. It is larger than Ras because the actual series resistance is only one source of the total loss (usually a small part). The Series Equivalent Circuit At one frequency, a measurement of complex impedance gives two numbers, the real part and the imaginary part: Z = Rs + jXs. At that frequency, the impedance behaves like a series combination of an ideal resistance Rs and an ideal reactance Xs (Figure 1). Rs RS XS CS Figure 1: Equivalent series circuit representation If Xs is negative, the impedance is capacitive, and the general reactance can be replaced with a capacitance of: −1 Cs = ωXs We now have an equivalent circuit that is correct only at the measurement frequency. The resistance of this equivalent circuit is the equivalent series resistance ESR = Rs = Real part of Z © IET LABS, Inc., September 2019 Printed in U.S.A 035002 Rev. A4 1 of 5 Application Note 2 of 5 Add the dissipation FACTOR energy lost Real part of Z If we define the dissipation factor D as D = = energy stored (− Imaginary part of Z) Rs Then D = =Rsω C = (ESR) ω C (− )Xs If one took a pure resistance and a pure capacitance and connected them in series, then one could say that the ESR of the combination was indeed equal to the actual series resistance. -
Supercapacitor Power Management Module Michael Brooks Santa Clara University
Santa Clara University Scholar Commons Electrical Engineering Senior Theses Student Scholarship 7-16-2014 Supercapacitor power management module Michael Brooks Santa Clara University Anderson Fu Santa Clara University Brett Kehoe Santa Clara University Follow this and additional works at: http://scholarcommons.scu.edu/elec_senior Part of the Electrical and Computer Engineering Commons Recommended Citation Brooks, Michael; Fu, Anderson; and Kehoe, Brett, "Supercapacitor power management module" (2014). Electrical Engineering Senior Theses. Paper 7. This Thesis is brought to you for free and open access by the Student Scholarship at Scholar Commons. It has been accepted for inclusion in Electrical Engineering Senior Theses by an authorized administrator of Scholar Commons. For more information, please contact [email protected]. Supercapacitor Power Management Module BY Michael Brooks, Anderson Fu, and Brett Kehoe DESIGN PROJECT REPORT Submitted in Partial Fulfillment of the Requirements For the Degree of Bachelor of Science in Electrical Engineering in the School of Engineering of Santa Clara University, 2014 Santa Clara, California ii Table of Contents Signature Page. .i . Title Page. ii Table of Contents. iii Abstract. v Acknowledgements . .vi 1 Introduction . …………………… 1 1.1 Core Statement . …………1 1.2 Supercapacitors and Energy Storage . ………......3 1.3 Design Goal . …………… 3 1.4 Design Considerations . …4 1.5 Module Overview . ……...6 Design of Module 2 Charge Management . 8 2.1 Choosing a Supercapacitor . …8 2.2 Safely Charging Supercapacitors. 9 2.3 Voltage Balancing Circuit. 10 2.4 Charge Sources . 11 3 Output Utilization. 13 3.1 Single Ended Primary Inductor Converter. …13 3.2 LT3959: Compensated SEPIC Feedback Controller . .13 3.3 SEPIC Topology . -
Agilent Basics of Measuring the Dielectric Properties of Materials
Agilent Basics of Measuring the Dielectric Properties of Materials Application Note Contents Introduction ..............................................................................................3 Dielectric theory .....................................................................................4 Dielectric Constant............................................................................4 Permeability........................................................................................7 Electromagnetic propagation .................................................................8 Dielectric mechanisms ........................................................................10 Orientation (dipolar) polarization ................................................11 Electronic and atomic polarization ..............................................11 Relaxation time ................................................................................12 Debye Relation .................................................................................12 Cole-Cole diagram............................................................................13 Ionic conductivity ............................................................................13 Interfacial or space charge polarization..................................... 14 Measurement Systems .........................................................................15 Network analyzers ..........................................................................15 Impedance analyzers and LCR meters.........................................16 -
100“ 168\A166\1::: 1:1 162 { 164C 1
US 20060180895Al (19) United States (12) Patent Application Publication (10) Pub. No.: US 2006/0180895 A1 Chen et al. (43) Pub. Date: Aug. 17, 2006 (54) CAPACITOR DEVICE WITH VERTICALLY (21) Appl. No.: 11/055,933 ARRANGED CAPACITOR REGIONS OF VARIOUS KINDS (22) Filed: Feb. 11, 2005 (75) Inventors: Yueh-You Chen, Hsin-Chu City (TW); Publication Classi?cation Chung-Long Chang, Dou-Liu city (TW); Chih-Ping Chao, Chu-Dong (51) Int. Cl. Town (TW); Chun-Hong Chen, Jhubei H01L 29/93 (2006.01) City (TW) (52) U.S. Cl. .......................................... .. 257/595; 257/E2l Correspondence Address: (57) ABSTRACT DUANE MORRIS, LLP IP DEPARTMENT A capacitor device selectively combines MOM, MIM and 30 SOUTH 17TH STREET varactor regions in the same layout area of an IC. TWo or PHILADELPHIA, PA 19103-4196 (US) more types of capacitor regions arranged vertically on a substrate to form the capacitor device. This increase the (73) Assignee: Taiwan Semiconductor Manufacturing capacitance per unit of the capacitor device, Without occu Company, Ltd. pying an extra layout area. 100“ 168\A166\1::: 1:1 162 { 164C 1:: . 160 158, F I /_\~ ’/'_‘\ 130 Bi- - + - +--E6_,154 /\_ A/A\ 128 i. - + - +--?, 152 122 ' 134 . ,/—\ 142 126 \_/—'—~ . + .. +_-\_, 150 /\'_ ‘/_\ 4 124 i. + - +--—2, 148 120% 118/1- ] 116f 108 112 112 104 10s \ p — /_/ 106 _ m _ 114 l_/114 110 Patent Application Publication Aug. 17, 2006 Sheet 2 0f 2 US 2006/0180895 A1 200“ - + - + + - + - - + - + + - + - FIG. 2 300% 316% + ' + 314“ 312% + + 310v“ ' 308 “w - + - + 306\___ 304“ + + FIG. 3 US 2006/0180895 A1 Aug. -
Application Note: ESR Losses in Ceramic Capacitors by Richard Fiore, Director of RF Applications Engineering American Technical Ceramics
Application Note: ESR Losses In Ceramic Capacitors by Richard Fiore, Director of RF Applications Engineering American Technical Ceramics AMERICAN TECHNICAL CERAMICS ATC North America ATC Europe ATC Asia [email protected] [email protected] [email protected] www.atceramics.com ATC 001-923 Rev. D; 4/07 ESR LOSSES IN CERAMIC CAPACITORS In the world of RF ceramic chip capacitors, Equivalent Series Resistance (ESR) is often considered to be the single most important parameter in selecting the product to fit the application. ESR, typically expressed in milliohms, is the summation of all losses resulting from dielectric (Rsd) and metal elements (Rsm) of the capacitor, (ESR = Rsd+Rsm). Assessing how these losses affect circuit performance is essential when utilizing ceramic capacitors in virtually all RF designs. Advantage of Low Loss RF Capacitors Ceramics capacitors utilized in MRI imaging coils must exhibit Selecting low loss (ultra low ESR) chip capacitors is an important ultra low loss. These capacitors are used in conjunction with an consideration for virtually all RF circuit designs. Some examples of MRI coil in a tuned circuit configuration. Since the signals being the advantages are listed below for several application types. detected by an MRI scanner are extremely small, the losses of the Extended battery life is possible when using low loss capacitors in coil circuit must be kept very low, usually in the order of a few applications such as source bypassing and drain coupling in the milliohms. Excessive ESR losses will degrade the resolution of the final power amplifier stage of a handheld portable transmitter image unless steps are taken to reduce these losses. -
IEEE Std 3002.3™-2018 Recommended Practice for Conducting Short-Circuit Studies and Analysis of Industrial and Commercial Power Systems
IEEE 3002 STANDARDS: POWER SYSTEMS ANALYSIS IEEE Std 3002.3™-2018 Recommended Practice for Conducting Short-Circuit Studies and Analysis of Industrial and Commercial Power Systems IEEE Std 3002.3™-2018 IEEE Recommended Practice for Conducting Short-Circuit Studies and Analysis of Industrial and Commercial Power Systems Sponsor Technical Books Coordinating Committee of the IEEE Industry Applications Society Approved 27 September 2018 IEEE-SA Standards Board Abstract: Activities related to short-circuit analysis, including design considerations for new systems, analytical studies for existing systems, as well as operational and model validation considerations for industrial and commercial power systems are addressed. Fault current calculation and device duty evaluation is included in short-circuit analysis. Accuracy of calculation results primarily relies on system modeling assumptions and methods used. The use of computer-aided analysis software with a list of desirable capabilities recommended to conduct a modern short-circuit study is emphasized. Examples of system data requirements and result analysis techniques are presented. Keywords: ac decrement, asymmetrical fault current, available fault current, bolted fault, breaking capacity, breaking duty, data collection, dc component, dc decrement, dc offset, device duty calculation, fault calculation, fault duty, IEEE 3002.3, interrupting capacity, interrupting duty, making capacity, making duty, momentary capacity, momentary duty, short-circuit analysis, short- circuit current, short-circuit studies, short-circuit withstand, symmetrical component, symmetrical fault current, system modeling, system validation, X/R ratio • The Institute of Electrical and Electronics Engineers, Inc. 3 Park Avenue, New York, NY 10016-5997, USA Copyright © 2019 by The Institute of Electrical and Electronics Engineers, Inc. All rights reserved.