PMU I2C 47K Pullups not great

Werner Almesberger werner at
Wed Feb 6 15:22:53 CET 2008

While we're fixing resistors, perhaps we could also change R1526:
it's 100k, so at I_IL(min) = -10uA, it would drop 1V, which is more
than V_IL(max) = 0.8V, not even taking into account tolerances.

(Page 25-4 of the S3C2442B User's Manual.)

This probably doesn't cause any problem in real life, but then you
never know ...

Anything in the 10k ... 47k range should work nicely. The pull-ups
there are all good. We'd just have to remember to make them smaller
if and when they're turned into pull-downs.

(R1526 is used for ID purposes, so we can't just use an internal
pull-down. Or if we did, we would have to lower the pull-ups into
the <= 18kOhm range.)

- Werner

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