RE: Plagued by Pull-up Resistors

[Jim Wickenhiser <jim.wickenhiser@vicom.com>]

Andy,

Thanks for your response.  I did notice that after much toil.  In fact 10ľA
is the number I ended up using by inference, but I now feel better using it
with outside confirmation.  Thanks.

Regards,
Jim Wick

-----Original Message-----
From: Ingraham, Andrew [mailto:Andrew.Ingraham@hp.com]
Sent: Wednesday, June 19, 2002 10:21 AM
To: Jim Wickenhiser
Cc: pci-sig@znyx.com
Subject: RE: Plagued by Pull-up Resistors


Hopefully you have found the answer to this question by now.  But in case
you haven't....

You were looking for "Iih", the Input High Leakage Current, in the 3.3V
signaling environment.  And it is true that there is no parameter by that
name ("Iih") in the 3.3V tables.

It just happens that the 5V table has a separate "Iih" and "Iil", but the
slightly newer 3.3V table combines the two into a single Input Leakage
Current spec, which (unfortunately?) also goes by the symbol "Iil" (where L
is for Leakage, rather than Low as it was in the 5V table).

In the Rmax equation in section 4.3.3, you should use Iih = 10uA for 3.3V
signaling.

Yes, it seems not every "i" was dotted and every "t" crossed.

Regards,
Andy


> ----------
> The spec provides Iih value for 5V (70ľA) in table 4-1 under section
> '4.2.1.1 DC Specifications' (pg. 117) but I can't find the corresponding
> value under the 3.3V section.
>