RE: Plagued by Pull-up Resistors

["Ingraham, Andrew" <Andrew.Ingraham@hp.com>]

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.
>