Q: When we have 5V present, StatusB reads 0x08 which indicated that CHGIN is present and valid and is the expected result. When we removed CHGIN 5V StatusB reads 0x20, which indicates that the CHGIN input current limit has been reached. The current limit should not be in effect since there should be no current - CHGIN is 0V. Is this expected behavior?
A: This behavior is expected. The explanation is that there is an analog loop on the charger/power path that actively reduces the charge current in order to keep SYS from drooping in a case where the wall adapter is too weak and starts collapsing. When you unplug the charger that loop saturates and gives an ILIM status. Of course it’s meaningless because the current limiter is off at that point. We will update the data sheet to explain this, but in the meantime know that this is indeed expected behavior.