Design of Voltage Selectable Circuit based on Power Mux for Charger IC

Abstract

This paper proposes Selectable Voltage Genrator. In order to supply a stable power supply voltage, a linear regulator LDO was used. The entire system in which this circuit is used is divided into Charging Mode and Discharging Mode. Charging Mode is the mode to charge the battery with USB voltage (VBUS), and the Discharging Mode is the mode to charge the USB voltage with the battery voltage (VBAT). The input voltage of VBUS is 2.7 ~ 20 V, The input voltage of VBAT supports up to 4 battery cells, The voltage of 1 cell is 4.2 V. According to the suggested input voltage, the voltage supplied into the chip is divided into 5V LDO and 3.3V LDO.