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ATS9350 ATS9350 500MS/S 12-Bit PCI Express Digitizer 500MS/S 12-Bit PCI Express Digitizer

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ATS9350 ATS9350 500MS/S 12-Bit PCI Express Digitizer 500MS/S 12-Bit PCI Express Digitizer ATS9350 ATS9350 500MS/s 12-Bit PCI Express Digitizer 500MS/s 12-Bit PCI Express Digitizer • 1.6 GB/s PCI Express (8-lane) interface • 2 channels sampled at 12-bit resolution • 500 MS/s real-time sampling rate • Variable frequency external clocking • Up to 2 GigaSample dual-port memory • Optional FPGA-based FFT • ±40mV to ±4V input range • Asynchronous DMA device driver • AlazarDSO oscilloscope software • Software Development Kit supports C/C++, C#, MATLAB and LabVIEW • Linux driver available Operating Sampling Memory Per Product Bus Channels Bandwidth Resolution System Rate Channel ATS9350 PCIe x8 Win XP/Vista/7, 2 500 MS/s 250 MHz Up to 2 Gig in 12 bits Linux 2.6+ to 2 MS/s single channel 32bit/64 bit mode Overview Applications ATS9350 is an 8-lane PCI Express (PCIe x8), dual- channel, high speed, 12 bit, 500 MS/s waveform Optical Coherence Tomography (OCT) digitizer card capable of streaming acquired data to Ultrasonic & Eddy Current NDT/NDE PC memory at rates up to 1.6 GB/s or storing it in its deep on-board dual-port acquisition memory buffer Radar/RF Signal Recording of up to 2 Gigasamples. Terabyte Storage Oscilloscope Up to four ATS9350 boards can be configured as a High Resolution Oscilloscope Master/Slave system to create a simultaneous sam- Lidar pling system of up to 8 input channels. Spectroscopy Unlike other products on the market, ATS9350 does Multi-Channel Transient Recording not use interleaved sampling. Each input has its own 12-bit, 500 MSPS ADC chip. Optional variable frequency external clock allows oper- ation from 500 MHz down to 2 MHz, making ATS9350 an ideal waveform digitizer for OCT applications. Users can capture data from one trigger or a burst of triggers. Users can also stream very large datasets continuously to PC memory or hard disk. ATS9350 is supplied with AlazarDSO software that lets the user get started immediately without having to go through a software development process. Users who need to integrate the ATS9350 in their own program can purchase a software development kit, ATS-SDK for C/C++ and MATLAB, or ATS-VI for LabVIEW for Windows or a Linux based ATS-Linux for C/C++ and LabVIEW for Linux. All of this advanced functionality is packaged in a low power, half-length PCI Express card. w w w . a l a z a r t e c h . c o m Version 2.0a ATS9350 500MS/s 12-Bit PCI Express Digitizer PCI Express Bus Interface An acquisition can consist of multiple records, with ATS9350 interfaces to the host computer using an each record being captured as a result of one trigger 8-lane PCI Express bus. Each lane operates at 2.5 event. A record can contain both pre-trigger and Gbps. PCIe bus specification v1.0a and v1.1 are post-trigger data. supported. Infinite number of triggers can be captured by According to PCIe specification, an 8-lane board can ATS9350, when it is operating using dual-port be plugged into any 8-lane or 16-lane slot, but not memory. into a 4-lane or 1-lane slot. As such, ATS9350 re- quires at least one free 8-lane or 16-lane slot on the In between the multiple triggers being captured, the motherboard. acquisition system is re-armed by the hardware within 256 sampling clock cycles. The physical and logical PCIe x8 interface is provided by an on-board FPGA, which also integrates acquisi- This mode of capture, sometimes referred to as tion control functions, memory management functions Multiple Record, is very useful for capturing data and acquisition datapath. This very high degree of in applications with a very rapid or unpredictable integration maximizes product reliability. trigger rate. Examples of such applications include medical imaging, ultrasonic testing, OCT and NMR PCI Express is a relatively new bus and, as such, spectroscopy. throughput performance may vary from motherboard to motherboard. AlazarTech’s 1.6 GB/s benchmark On-Board Acquisition Memory was done on an ASUS P6T7 motherboard based on ATS9350 supports on-board memory buffers of 128 the x58 chipset for iCore processors. Megasamples, 1 Gigasamples and 2 Gigasamples. Other motherboards. such as Intel S5000PSL, pro- Acquisition memory can either be divided equally duced similar results, whereas older machines such between the two input channels or devoted entirely as the Dell T7400 also support 1.6 GB/s. to one of the channels. Users must always be wary of throughput specifica- There are two distinct advantages of having on-board tions from manufacturers of waveform digitizers. memory: Some unscrupulous manufacturers tend to specify the First, a snapshot of the ADC data can be stored into raw, burst-mode throughput of the bus. AlazarTech, this acquisition memory at full acquisition speed of 2 on the other hand, specifies the benchmarked sus- ch * 500 MS/s * 2 bytes per sample = 2 Gigabytes tained throughput. To achieve such high throughput, per second, which is higher than the maximum PCIe a great deal of proprietary memory management logic x8 bus throughput of 1.6 GB/s. and kernel mode drivers have been designed. Second, and more importantly, on-board memory Analog Input can also act as a very deep FIFO between the Analog An ATS9350 features two analog input channels with to Digital converters and PCI Express bus, allowing extensive functionality. Each channel has up to 250 very fast sustained data transfers across the bus, MHz of full power analog input bandwidth. Note that even if the operating system or another motherboard the bandwidth is reduced to 150 MHz for the ±40mV resource temporarily interrupts DMA transfers. range. Maximum Sustained Transfer Rate With software selectable attenuation, you can achieve PCI Express support on different motherboards is not an input voltage range of ±40mV to ±4V. always the same, resulting in significantly different It must be noted that input impedance of both chan- sustained data transfer rates. The reasons behind nels is fixed at 50Ω. these differences are complex and varied and will not be discussed here. Software selectable AC or DC coupling further in- creases the signal measurement capability. ATS9350 users can quickly determine the maximum sustained transfer rate for their motherboard by Acquisition System inserting their card in a PCIe slot and running the ATS9350 PCI Express digitizers use state of the art Tools:Benchmark:Bus tool provided in AlazarDSO 500 MSPS, 12-bit ADCs to digitize the input signals. software. The real-time sampling rate ranges from 500 MS/s ATS9350, which is equipped with dual-port on-board down to 1 KS/s for internal clock and 2 MS/s for ex- memory, will be able to achieve this maximum sus- ternal clock. tained transfer rate. The two channels are guaranteed to be simultaneous, as the two ADCs use a common clock. Version 2.0a w w w . a l a z a r t e c h . c o m ATS9350 ATS9350 500MS/s 12-Bit PCI Express Digitizer 500MS/s 12-Bit PCI Express Digitizer Recommended Motherboards TRIGGER Many different types of motherboards have been benchmarked by AlazarTech. The best performance INPUT(S) is provided by motherboards that use the Intel x58 chipset and iCore 7 processors. The motherboard that CAPTURE Record 1 Record N Record N+1 has consistently given the best throughput results (as high as 1.7 GB/s) has been te ASUS P6T7. TRANSFER TO PC DMA 1 (includes Records 1 to N) Older motherboards, such as Intel S5000PSLSATA that use the S5000 chipset have also provided very Note that a DMA is not started until RecordsPerBuffer good (1.6 GB/s) throughput. number of records (triggers) have been acquired and written to the on-board memory. It should be noted that some motherboards may behave unexpectedly. For example, one customer NPT AutoDMA buffers do not include headers, so it is purchased a P6T6 motherboard (instead of P6T7) not possible to get trigger time-stamps. and found that the throughput was limited to ap- proximately 800 MB/s because P6T6 only supports More importantly, a BUFFER_OVERFLOW flag is as- 4-lane PCI Express connection, even though it uses serted only if the entire on-board memory is used up. the same x58 chipset. This provides a very substantial improvement over Traditional AutoDMA. Traditional AutoDMA In order to acquire both pre-trigger and post-trigger NPT AutoDMA can easily acquire data to PC host data in a dual-ported memory environment, users can memory at the maximum sustained transfer rate of use Traditional AutoDMA. the motherboard without causing an overflow. This is the recommended mode of operation for most TRIGGER ultrasonic scanning, OCT and medical imaging ap- INPUT(S) plications. CAPTURE Record 1 Record 2 Record 3 Continuous AutoDMA Continuous AutoDMA is also known as the data streaming mode. TRANSFER TO PC DMA 1 DMA 2 DMA 3 In this mode, data starts streaming across the PCI Data is returned to the user in buffers, where each bus as soon as the ATS9350 is armed for acquisition. buffer can contain from 1 to 8191 records (triggers). It is important to note that triggering is disabled in This number is called RecordsPerBuffer. this mode. Users can also specify that each record should come START CAPTURE with its own header that contains a 40-bit trigger INPUT(S) timestamp. CAPTURE A BUFFER_OVERFLOW flag is asserted if more than TL captured 2 * TL captured 3 * TL Captured 512 buffers have been acquired by the acquisition system, but not transferred to host PC memory by TRANSFER TO PC DMA 1 DMA 2 DMA 3 the AutoDMA engine.
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