FPGA Central - World's 1st FPGA / CPLD Portal

FPGA Central

World's 1st FPGA Portal

 

Go Back   FPGA Groups > NewsGroup > FPGA

FPGA comp.arch.fpga newsgroup (usenet)

Reply
 
LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 02-07-2008, 01:29 PM
taco
Guest
 
Posts: n/a
Default Prom alternatives for xilinx

We are want to use a spartan 3E in the very small chip scale package because
of space constraints. However the 4 MBit serial prom for this device is
almost the same size as the whole fpga. Does anybody know of an alternative
which is much smaller?
Taco Walstra
University of Amsterdam
Reply With Quote
  #2 (permalink)  
Old 02-07-2008, 02:14 PM
Gabor
Guest
 
Posts: n/a
Default Re: Prom alternatives for xilinx

On Feb 7, 8:29 am, taco <[email protected]> wrote:
> We are want to use a spartan 3E in the very small chip scale package because
> of space constraints. However the 4 MBit serial prom for this device is
> almost the same size as the whole fpga. Does anybody know of an alternative
> which is much smaller?
> Taco Walstra
> University of Amsterdam


1) Don't know how much this helps, but if you're using the
3S500E and don't fill the part up too much, your bitstream
can fit into a 2 Mbit prom if you compress it. Banking on
that however can lead to problems if your design expands and
the compressed bitstream grows over the 2 Mbit boundary.

2) Do you have some other storage available that could be
shared to with the bitstream data? A microcontroller
with attached flash? A 120 Gbyte hard drive attached
via the host system interface? Or does your FPGA need to
come up running without any support from software?

3) Any chance of using a Lattice XP2 in the 132-ball csBGA
instead (no external prom required)?
Reply With Quote
  #3 (permalink)  
Old 02-07-2008, 02:22 PM
Antti
Guest
 
Posts: n/a
Default Re: Prom alternatives for xilinx

On 7 Feb., 14:29, taco <[email protected]> wrote:
> We are want to use a spartan 3E in the very small chip scale package because
> of space constraints. However the 4 MBit serial prom for this device is
> almost the same size as the whole fpga. Does anybody know of an alternative
> which is much smaller?
> Taco Walstra
> University of Amsterdam


there are QFN versions of SPI flash available, they much smaller.
I also have a desing where SO-8 package is HIGHEST component
and almost the same size as QFN132 packaged FPGA.
I used SO-8 as it is few cent cheaper than QFN SPI flash.

Antti Lukats
Reply With Quote
  #4 (permalink)  
Old 02-08-2008, 07:41 AM
taco
Guest
 
Posts: n/a
Default Re: Prom alternatives for xilinx

Gabor wrote:

>
> 1) Don't know how much this helps, but if you're using the
> 3S500E and don't fill the part up too much, your bitstream
> can fit into a 2 Mbit prom if you compress it. Banking on
> that however can lead to problems if your design expands and
> the compressed bitstream grows over the 2 Mbit boundary.

I don't know yet if it fits in a 2 MBit prom because it depends on some
cores not yet written. what do you mean with 'compress'? There is no
processor available for some kind of uncompressing it during power up, the
fpga should just 'boot' from the prom.

>
> 2) Do you have some other storage available that could be
> shared to with the bitstream data? A microcontroller
> with attached flash? A 120 Gbyte hard drive attached
> via the host system interface? Or does your FPGA need to
> come up running without any support from software?


no not really a 120 GB drive available. The whole system should be fitted on
a few cm.flexprint, the microcontroller/RAM etc. is part of the FPGA.


>
> 3) Any chance of using a Lattice XP2 in the 132-ball csBGA
> instead (no external prom required)?


Mm, good tip. I'll investigate that line. thanks.
Taco
Reply With Quote
  #5 (permalink)  
Old 02-09-2008, 07:24 PM
Walter
Guest
 
Posts: n/a
Default Re: Prom alternatives for xilinx

On 7 feb, 10:29, taco <[email protected]> wrote:
> We are want to use a spartan 3E in the very small chip scale package because
> of space constraints. However the 4 MBit serial prom for this device is
> almost the same size as the whole fpga. Does anybody know of an alternative
> which is much smaller?
> Taco Walstra
> University of Amsterdam


check at Xilinx web for the Spartan 3AN.
Reply With Quote
  #6 (permalink)  
Old 02-09-2008, 09:31 PM
Antti
Guest
 
Posts: n/a
Default Re: Prom alternatives for xilinx

On 9 Feb., 20:24, Walter <[email protected]> wrote:
> On 7 feb, 10:29, taco <[email protected]> wrote:
>
> > We are want to use a spartan 3E in the very small chip scale package because
> > of space constraints. However the 4 MBit serial prom for this device is
> > almost the same size as the whole fpga. Does anybody know of an alternative
> > which is much smaller?
> > Taco Walstra
> > University of Amsterdam

>
> check at Xilinx web for the Spartan 3AN.


S3-AN is not availalable in small packages
so s3e-132+qfn flash take less space than smallest s3an

Antti
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
is there any opensource alternatives to platformstudio and microblaze development? CMOS FPGA 4 04-10-2007 06:30 PM
Xilinx PROM maxascent FPGA 3 05-01-2006 02:15 PM
Nuhorizons alternatives for Xilinx parts? dlharmon FPGA 1 04-29-2005 08:03 PM
Cheap alternatives to Mach 210s Fred FPGA 4 03-08-2005 09:12 AM
alternatives to xst-map Jan Bruns FPGA 3 10-20-2004 06:23 AM


All times are GMT +1. The time now is 11:46 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.2.0
Copyright 2008 @ FPGA Central. All rights reserved