A single-inductor dual-input dual-output buck regulator with enhanced power-delivery capability for portable battery management system

A single-inductor dual-input dual-output (SIDIDO) buck regulator is presented for simultaneously regulating a battery charging current and a output DC voltage in portable battery management system. The proposed SIDIDO converter operates in the continuous-conduction mode for relaxing the peak current stress and thus enables the converter to deliver a maximum load power of 2.2 W. Moreover, the cross regulation between two outputs is minimized due to fast dynamic response provided by the current-mode control at a switching frequency of 2.5 MHz. The proposed SIDIDO converter was designed using a 0.35-μm standard CMOS process. Results show that the converter not only regulates the charging current up to 300 mA with Li-Ion battery voltage ranging from 2.7 V to 4.2 V, but also provides a regulated output voltage with a maximum 400 mA load current. The cross regulation between two outputs is less than 0.18 mV/mA.