Let me make clear that I don't have any specific opposition to FMC for the power/digital signals. The only reason for considering other types of connectors would be either if the desired stackup height is not doable (this is unlikely -- one .224" bullet e.g. corning A1A1-0001-02, plus two male connetors with .051" reference plane distance, e.g. Molex 74315-3312, gives a total SMP height of 8.28 mm, which works perfectly with the standard FMC stackup height of 8.5 mm board to board), or if there is not enough real estate on the board to meet the physical footprint requirements (FMC is larger than the QSE connectors I sent along, for example).
> -----Original Message----- > From: Robert Jördens [mailto:r...@m-labs.hk] > Sent: Tuesday, March 29, 2016 11:08 AM > To: Slichter, Daniel H. (Fed) <daniel.slich...@nist.gov> > Cc: Sébastien Bourdeauducq <s...@m-labs.hk>; Grzegorz Kasprowicz > <gkasp...@elka.pw.edu.pl>; artiq@lists.m-labs.hk > Subject: Re: [ARTIQ] FW: initial specification of the project > > On Tue, Mar 29, 2016 at 5:16 PM, Slichter, Daniel H. (Fed) > <daniel.slich...@nist.gov> wrote: > > Yes, FMC could work but it's overkill in terms of pin count; one might be > able to find a smaller footprint connector with fewer pins, which would be > advantageous. Frankly something as dumb and cheap as 2 mm pin headers > would do the job. > > Yes. A pin header would be dumb if there are better suggestions. > LPC FMC with 64 single ended signals is definitely not overkill if 40 signals > is > the estimated need. The grounding is unlikely to hurt. > There are certainly many other offers. But if there is such a strong > opposition > to FMC, I would look for something where we can at least expect a long term > availability that is similar to the FMC usage lifespan. _______________________________________________ ARTIQ mailing list https://ssl.serverraum.org/lists/listinfo/artiq
