Hello all,
My team and I are working an a very low power design that involves a hardware shutdown of the majority of the circuitry after the voltage has dropped to a certain level. The BQ76920 is a part of said circuitry, so BAT and REGSRC are disconnected from power in this event and left to float. The cell connections including VC0, and VSS remain in tact.
It seems, however, that there is a leakage path from one of the cells to BAT or REGSRC (they are shorted together on our PCB) because when power is removed, BAT and REGSRC float up to about 60% of the total cell stack voltage. This is not good because this leakage path has enough power to end up powering some of the circuitry that we are intending to shut off that is on the same power node.
Are there protection diodes of some sort in the chip that could explain this? We need to get around this but want to make sure we attack the problem correctly.
Thanks,
Nino
