Spartan 3 POR Spec?

[Steve Smith]

I'm looking at designing with Spartan 3. The data sheet says the
power-on-reset timing ranges from 5-7ms. Does anyone have any design
tips/suggestions for meeting this spec? Anything I should watch out
for?

 

[John Adair]

Registers are usually reset/set as part of configuration. It depends on the
types of registers implemented.

However you can also use the DONE signal to drive an external reset chip
that will extend the reset beyond configuration by an amount. There also
some logic configurations that you can use to add a delay beyond
configuration.

If you are worried about DLL lockup you can gate the locked signals into a
reset signal.

--
John Adair
Enterpoint Ltd.
http://www.enterpoint.co.uk

This message is the personal opinion of the sender and not that necessarily
that of Enterpoint Ltd.. Readers should make their own evaluation of the
facts. No responsibility for error or inaccuracy is accepted.


"Steve Smith" <stevesmith_98@yahoo.com> wrote in message
news:5da07ec1.0404151930.498c5fa7@posting.google.com...

I'm looking at designing with Spartan 3. The data sheet says the
power-on-reset timing ranges from 5-7ms. Does anyone have any design
tips/suggestions for meeting this spec? Anything I should watch out
for?