Hi Team,
one of my customer has following question regards PCA9554A.
----------------------------------------------
In one of our new designs we are using the PCA9554ABRGVR as GPIO expander.
The IC always responds with a NACK.
We have checked with oscilloscope and the signal is OK.
The address we are using is 0x70. A0,A1 and A2 are grounded.
Do you know why we cannot communicate with the IC?
Is there any special start-up sequence that we need to send?
Do you know what we can do?
The SCL and SDA signals are pulled up with 10K resistors.
------------------------------
Could you please help?
Thanks and regards
Martin
