Hi Jonathan, On Mon, 9 May 2022 at 17:26, 'Jonathan Weintroub' via [email protected] <[email protected]> wrote:
> Hi CASPERites, > > At SAO we’ve been developing high performance instruments based on the > Xilinx VCU128 evaluation board > <https://www.xilinx.com/products/boards-and-kits/vcu128.html> and the Adsantec > ASNT7123A <https://www.adsantec.com/product/asnt7122-kma-2-2/> 16 GS/s > 4-bit direct flash ADC. Currently VCU128 is currently priced at > $10,794/each (it’s gone up a bit like everything but this is still good or > even incredible value) and the lead time per the prior page is 2-weeks, > essentially ex-stock. Some time ago I had discussions with Xilinx and > various distributors, and there was no obstruction to buying multiple piece > quantities of the eval board. Though its not the last word on acquisition > I’ll note that the XCVU37P-L2FSVH2892E, a very large and high performance > DSP oriented Ultrascale+ FPGA with 8GB of HBM and 9,024 DSP slices, is > listed at $90,786 and no lead time quoted (though I hear 12 months is not > uncommon for FPGAs these days) at Digikey > <https://www.digikey.com/en/products/detail/xilinx-inc/XCVU37P-L2FSVH2892E/10445689?utm_adgroup=Integrated%20Circuits&utm_source=google&utm_medium=cpc&utm_campaign=Dynamic%20Search_EN_Product&utm_term=&utm_content=Integrated%20Circuits&gclid=CjwKCAjw9-KTBhBcEiwAr19ig1z2w2nm58KUOcpYNY7njQ4XD2Ey-swFM0q8XFGSD_3hEU9LJdEwyxoCDEkQAvD_BwE> > and > other distributors. > > While our development with VCU128 has been very successful in terms of > validating ADC performance, developing 100 Gbps Ethernet and various > application firmware codes, we are hitting a variety of reliability and > related issues with the VCU128. There is a bit of a laundry list of these, > following are examples: The 1 Gbps Ethernet control port doesn’t always > come up reliably and loading of FPGA codes can be intermittent on > power-up. Looking more at electromechanical, we have concerns that the > FMC+ high speed connector (which we use to connect a “mezzanine” ADC board > to the FPGA) is not mechanically robust, and has no built in positive > locking or similar mechanism. Also the eval board has quite of lot of > circuitry we don’t need, notably the PCIe bus and connector, not in of > itself a showstopper, however does interact with concerns we have about > thermal design of the PCB and the impact on the overall system. > > With all of the above as background, and noting that at one time the > VCU128 (and its predecessor the VCU118) has been suggested as a possibly > viable CASPER-supported solution (I vaguely recall there was at one time a > working group focused no eval boards generally), we are wondering what the > broader experience of the collaboration has been? Has any group been > successful at fielding a viable production instrument based on VCU128 or > other eval board? Do the experiences reported in the second paragraph > sound familiar to anyone? > > We are going down the path of custom hardware, but the addition of supply > chain delays, and the impressive pricing noted above causes us to pause to > poll for broader CASPER experiences. Also relevant here would be to hear > if there are any hardware developments (SKARAB2?) available to us and > potentially helpful? > The VCU128 is certainly well-priced, but I would note that I have been using the same vu37p FPGA in PCIe form-factor via the Alpha Data ADM-PCIe-9H7 board, which was (when I ordered 18 months ago) cheaper than the VCU128. I'm also quite enthusiastic about system-on-modules, which can deliver very good low-quantity prices without too much NRE to implement custom packaging. I've been playing with the iWave ZU11 SoM board with success so far. Without knowing your requirements regarding NRE, lead-time, etc, my first suggestion is to get in touch with a Xilinx-partnered vendor and start a conversation with them. Maybe someone has what you need already, or maybe they would consider it a small job to adapt one of their existing boards to your needs. But what is almost certainly true is that the costs you will be quoted will be nothing like the digikey chip prices. My personal opinion is that dev boards should be avoided in deployments (particularly in harsh environments) since Xilinx will no-doubt turn their back on you in the event you have issues. With a commercial vendor, you can at least lay out expectations for performance and tech support going into the project. I also find it hard to believe that it makes economic sense to design anything completely in-house and pay retail FPGA prices, unless you are big enough to have your own deal with Xilinx. Just my subjective and biased $0.02 though :) Jack > > I am working with various colleagues on this, notably Ranjani Srinivasan > and Rick Raffanti, and they may weigh in here to fill in details, or > correct anything I got wrong. But I hope the intent here is clear, not to > get into the nitty gritty right away, but rather to discuss the bigger > picture of viability of use of eval boards. > > Thanks for reading and thinking about this, and best wishes, > > Jonathan Weintroub > > > > > > > > > > > > > > -- > You received this message because you are subscribed to the Google Groups " > [email protected]" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/F206962E-E777-473C-85B6-A502CBDBCF28%40cfa.harvard.edu > <https://groups.google.com/a/lists.berkeley.edu/d/msgid/casper/F206962E-E777-473C-85B6-A502CBDBCF28%40cfa.harvard.edu?utm_medium=email&utm_source=footer> > . > -- You received this message because you are subscribed to the Google Groups "[email protected]" group. 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