Hi Jonathan, Yes, I should mention our R2 FPGA is running at 30% resource utilization, so we only need ~40W total power for our R2s. There is a 160W 12V PicoPSU for larger designs, but nothing 250W rated.
Cheers, Brad Dober Ph.D. Candidate Department of Physics and Astronomy University of Pennsylvania Cell: 262-949-4668 On Fri, Jul 8, 2016 at 10:09 AM, Jonathan Weintroub < jweintr...@cfa.harvard.edu> wrote: > Hi Ben & Brad, > > Those certainly are interesting and inexpensive low profile ATX power > supplies, and it’s also interesting to see others are home brewing power > supply schemes for the ROACH2. Thanks for the reference—I’d be > interested, for example, to see if Mini Box Pico’s are available with Line > In. > > That said, I should point out that you have referenced 80W rated (@ input) > power supplies, whereas the ROACH2—depending on factors such as bit code > size, clock rate, which ADCs and how many SFP+ mezzanines are installed, > which of the on-board-off-FPGA resources such as DDR3, QDR and PPC are > used, and a derating factor for altitude (e.g. in Brad’s balloon, or in > our case on Mauna Kea) can definitely require a 250W rated ATX power supply > like the one specified. > > TLDR: 80W ATX PSU might work for a stripped down ROACH2 application, > still it is not an adequate worst case rating in general. > > Regards, > > Jonathan > > > > On Jul 7, 2016, at 5:32 PM, Brad Dober <do...@sas.upenn.edu> wrote: > > > > Those PicoPSUs shouldn't fail even under vacuum. > > We have flown them (specifically these: > http://www.mini-box.com/PicoPSU-80-WI-32V ) on a balloon payload twice > before. > > > > > > Brad Dober > > Ph.D. Candidate > > Department of Physics and Astronomy > > University of Pennsylvania > > Cell: 262-949-4668 > > > > On Thu, Jul 7, 2016 at 5:26 PM, <bma...@physics.ucsb.edu> wrote: > > > > We use a beefy 12V power supply and feed these: > > http://www.mini-box.com/picoPSU-80 > > > > They are very small and convenient. > > > > We have run 8 of them in our ROACH crate for probably a year of > integrated > > time without a failure. We have 10 in our new ROACH2 crate and we’ll see > > how they hold up there over the coming year. > > > > Ben > > __________________________________________________________________ > > Ben Mazin Phone/Fax: 805-893-3344 > > Associate Professor http://mazinlab.org > > Department of Physics Skype: bmazin.work > > University of California Office: 2015H Broida Hall > > Santa Barbara, CA 93106 USA Lab: 3509 Broida Hall > > > > > > > >
