What is the smallest resistance value of pull-up resistors for an I2C bus driving only PCF8575 chips?
I have a bunch of PCF8575 breakout boards (three to be exact) on one I2C network. Each with a 10K resistor, equivalent to a single 3.333k ohm resistor. I now appear to have one board that are no longer responding. Before I swap out the dead board out (again, already did once) I want to try to isolate the issue before I ruin a third board.