Spartan 3E

I plan to use a Spartan3E device, namely  XC3S500E-4PQG208C,
in my next project, but  there are several questions I would like to ask:

1. what is their performance (relatively to the older Spartan 3 stepping 4)

a) maximal clock frequency;
b) peak and average power consumption at 250MHz (Vcc, Vaux, Vio);
c) average mW/MHz;

2. can I use a multiplier and its "neighbour" BRAM simultaneously,
i.e. is there enough routing?

3. can I clock the device (preferably differential mode) using
a 50MHz sine, extremely pure clock? It's Vpp can be adjusted
to meet the requirements (what are they?).

    Best regards
    Piotr Wyderski

Piotr Wyderski <wyderski@mothers.against.spam-ii.uni.wroc.pl> wrote:
> I plan to use a Spartan3E device, namely  XC3S500E-4PQG208C,
> in my next project, but  there are several questions I would like to ask:

> 1. what is their performance (relatively to the older Spartan 3 stepping 4)

> a) maximal clock frequency;
> b) peak and average power consumption at 250MHz (Vcc, Vaux, Vio);
> c) average mW/MHz;

> 2. can I use a multiplier and its "neighbour" BRAM simultaneously,
> i.e. is there enough routing?

> 3. can I clock the device (preferably differential mode) using
> a 50MHz sine, extremely pure clock? It's Vpp can be adjusted
> to meet the requirements (what are they?).

First question to ask (if you are no really _big_ customer):

Where to I get XC3SE from?

-- 
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------

Uwe Bonnes wrote:

"> First question to ask (if you are no really _big_ customer):
> 
> Where to I get XC3SE from?

There is a small Polish shop which sells them:

http://www.kamami.pl/?id_k1=87&id_k2=76&id_k3=20

1 PLN = 0.26 Euro.

The largest device they have is 3S500, which costs 38,5 Euro @ 1
piece quantity. But I don't know whether they sell the chips outside
the country. Anyway, that's the reason I have decided to divorce
with Altera -- nobody sells their nice chips. :-(

    Best regards
    Piotr Wyderski

Piotr Wyderski <wyderski@mothers.against.spam-ii.uni.wroc.pl> wrote:
> Uwe Bonnes wrote:

> "> First question to ask (if you are no really _big_ customer):
> > 
> > Where to I get XC3SE from?

> There is a small Polish shop which sells them:

> http://www.kamami.pl/?id_k1=87&id_k2=76&id_k3=20

> 1 PLN = 0.26 Euro.

> The largest device they have is 3S500, which costs 38,5 Euro @ 1
> piece quantity. But I don't know whether they sell the chips outside
> the country. Anyway, that's the reason I have decided to divorce
> with Altera -- nobody sells their nice chips. :-(

Make sure they have them on stock. Every other lokation I have seen, that
lists them, state no explicit lead time. 

-- 
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------

Piotr Wyderski <wyderski@mothers.against.spam-ii.uni.wroc.pl> wrote:
>Uwe Bonnes wrote:

>"> First question to ask (if you are no really _big_ customer):
>> 
>> Where to I get XC3SE from?

>There is a small Polish shop which sells them:

>http://www.kamami.pl/?id_k1=87&id_k2=76&id_k3=20

>1 PLN = 0.26 Euro.

>The largest device they have is 3S500, which costs 38,5 Euro @ 1
>piece quantity. But I don't know whether they sell the chips outside
>the country. Anyway, that's the reason I have decided to divorce
>with Altera -- nobody sells their nice chips. :-(

www.elfa.se does, and they have office in Poland. For over the desk buying
if so required.
  http://www.elfa.se/pl/kontakt.html

Now if altera only had webpack for linux.. ;)

Piotr,

Since no one else seems to wish to answer your technical questions, I will:

see below

Austin

> 1. what is their performance (relatively to the older Spartan 3 stepping 4)
>

Almost identical.  3E uses the same process as 3.  The families are cost 
optimized for logic, and the other for IO.

> 2. can I use a multiplier and its "neighbour" BRAM simultaneously,
> i.e. is there enough routing?

The routing is the same as Spartan 3.  If you had problems before, then 
you will have them again (with a particular routing).  Not sure what you 
are trying to do.  There may be a different suggested way to solve the 
problem using these families' architecture.

> 3. can I clock the device (preferably differential mode) using
> a 50MHz sine, extremely pure clock? It's Vpp can be adjusted
> to meet the requirements (what are they?).

You may use a sine wave clock, but that will mean that you will have 
more jitter than if you use a square wave clock.  That has nbothing to 
do with Spartan 3E (or 3), it is just the fact that a sine wave is 
provides a vaying time if there is any ground bounce, Vcc bounce, cross 
talk, etc (which there always is).  I would suggest using the largest 
p-p sine wave you can get, if this is desired, then the transition 
through the zero crossing will be the fastest.  For example, if the 
differential input is in a 2.5V bank, a 2.5 V sine wave (rail to rail) 
is best as the LVDS input buffer slices at about 50 mV or less between + 
and -.

In article <e488iq$b1d6@xco-news.xilinx.com>, Austin Lesea wrote:
> >
> > 1. what is their performance relative to the older Spartan 3
> 
> Almost identical.  3E uses the same process as 3.  The families
> are cost optimized for logic, and the other for IO.

What I don't get is why the 3E "only" has such small devices if they
are trully logic optimized?  Personally, I would love to use a 208-pin
version of an FPGA with 4+ million "gates"...  My I/O requirements for
my current project are minimal... the logic requirements are somewhat
larger.

--Toby.

Tobias Weingartner schrieb:

> What I don't get is why the 3E "only" has such small devices if they
> are trully logic optimized?  Personally, I would love to use a 208-pin
> version of an FPGA with 4+ million "gates"...  My I/O requirements for
> my current project are minimal... the logic requirements are somewhat
> larger.

Maybe because you application is not the typical one, that was found by 
evaluating sales/custumer requirements.
A FPGA will never be a perfect match in IO, logic, whatever. Thats the 
"sacrifice" to flexibility.

Regards
Falk

Hi, Tobias,
Falk said it: we are not a boutique. Spartan, even more than Virtex, is
aimed at the high-volume market.
If you have peculiar requirements, you must make trade-offs. C'est la
vie.
Peter Alfke, Xilinx

Tobias Weingartner <weingart@cs.ualberta.ca> wrote:
> In article <e488iq$b1d6@xco-news.xilinx.com>, Austin Lesea wrote:
> > >
> > > 1. what is their performance relative to the older Spartan 3
> > 
> > Almost identical.  3E uses the same process as 3.  The families
> > are cost optimized for logic, and the other for IO.

> What I don't get is why the 3E "only" has such small devices if they
> are trully logic optimized?  Personally, I would love to use a 208-pin
> version of an FPGA with 4+ million "gates"...  My I/O requirements for
> my current project are minimal... the logic requirements are somewhat
> larger.

What about using some module, like the Zefants (www.zefant.de) or
the HydraX (http://www.hydraxc.com/)?
-- 
Uwe Bonnes                bon@elektron.ikp.physik.tu-darmstadt.de

Institut fuer Kernphysik  Schlossgartenstrasse 9  64289 Darmstadt
--------- Tel. 06151 162516 -------- Fax. 06151 164321 ----------