RE: New project...PCI based servo control board

["Craig Edwards" <cedwards-at-ceinetworks.com>]

I agree with the comments on choice of FPGAs...and yes, I'm pretty sure
we'll have to use 3.3V (really no reason not to that I'm aware of).
Actually, 5V is slated to disappear from the "desktop" PCI bus next
year....but of course that remains to be seen.  

Jon's right about older parts...mainstream FPGAs get designed into so many
smaller applications that they take long time before they really disappear.
Not nearly as bad as application specific parts, which can die pretty fast.
And when they do go end of life... The VHDL will just have to be
re-targeted.  

-Craig

-----Original Message-----
From: emc-at-nist.gov [emc-at-nist.gov] On Behalf Of Jon Elson
Sent: Friday, March 28, 2003 1:18 AM
To: Multiple recipients of list
Subject: Re: New project...PCI based servo control board





John Sheahan wrote:

>On Thu, Mar 27, 2003 at 09:55:41PM -0500, Craig Edwards wrote:
>  
>
>>Agreed.  With regard to long term availability we need to make sure 
>>the FPGA is built on a mainstream process that will be in high volume 
>>production for a long time.  Also, I prefer a non-volatile 
>>architecture, i.e. one which doesn't require a boot process during 
>>power up, but there is a cost trade-off with regard to SRAM based 
>>FPGAs.
>>
>>    
>>
>
>I think you will be doing really well to get more than perhaps 5 years
>availability from any fpga today.   There are no mainstream, long-life 
>processes any more.  Eg go back 8-10 years to the Xilinx 4000 - seems 
>to be no longer available.
>  
>
If you are building in 10,000 piece quantity, this is mostly true.  For 
the kinds of
projects discussed here, go with Xilinx, and their parts will be 
available for a LONG
time.  There are all sorts of brokers who have batches of ANCIENT Xilinx 
parts
they are still trying to get rid of.

>Choose the supply rail you want to use first,  work from there. If you 
>were to pick 5V (say) then don't expect more than a couple more years 
>methinks.
>  
>
Yup, the 5V stuff is going out of favor.

Jon