SLVSI59 April 2026 TPS61382A-Q1
PRODUCTION DATA
During SOH mode, the TPS61382A-Q1 fully turns on the isolation MOSFET Q3 and regulate the gate voltage of the low-side MOSFET Q2 with LO pin. In this way, low side MOSFET operates in saturation area and discharge the back up battery by constant current. TI recommend 500mA discharge current to achieve best accuracy. By sensing the battery open voltage, voltage with discharge current and discharge current, the battery internal resistance Rbatcan be given by:
where:
According to the recommendation from battery manufacturer , it is recommened to discharge battery with 500mA Idischg for 500ms and then read Vdischg