Power Management Control Circuit

摘要

A power management control circuit controls a first power transistor to convert a input voltage to an output voltage and controls a second power transistor to charge a battery from the output voltage. The first power transistor is coupled between the input voltage and the output voltage, and the second power transistor is coupled between the output voltage and the battery. The power management control circuit includes: a detection transistor detecting a current through the second power transistor and generating a charging reference voltage; an amplifier comparing the output voltage with the voltage of the battery to generate an amplified signal for controlling the charging reference voltage; a comparator comparing a reference voltage with the charging reference voltage to generate an EOC (End of Charge) signal for determining whether to stop charging the battery; and an offset voltage compensation device compensating an input offset voltage of the amplifier.