BQ25895: Turn off by I2C and power up with digital input

Hey Ricardo,

Are you trying to disable the VSYS voltage with an adapter present AND also in battery only mode?

If you are in battery only mode and want to disable VSYS, you can place the part in shipping mode to turn off the Q4 BATFET to isolate VSYS from VBAT. This helps reduce leakage current from VBAT to your system output. In this mode, you can re-enable the Q4 FET in two ways:
1) Applying an adapter
2) Using the QON pin of the charger and driving that with a digital input if desired.

However, in adapter mode, you can place the charger in HIZ to stop the buck converter that regulates VSYS via I2C, but you cannot use any external digital pin to re-enable the converter.


Regards,
Joel H