We found that this IC (bq24074) does not have a Low voltage protection (LVP) for the battery side. To implement LVP, external voltage measurement using a MCU can be done. MCU disables the IC by putting the SYSOFF pin high through a external pull up resistor. Now, as the V_OUT is off, then the external pull up does not have any voltage. The SYSOFF pin goes floating. In the datasheet it is mentioned that the SYSOFF pin has an internal pull up of 5MOhms. This is pulled up to Vbat. But there is no clear information given where the Vbat voltage comes from. The problem is - when the IC is disabled via SYSOFF pin, is there a need of external voltage to keep the IC disabled till an external power (USB or other power source via IN pin) is connected?
Any suggestions are appreciated.
Than you.
