An Integrated CMOS Current-Sensing Circuit for Low-Voltage Current-Mode Buck Regulator

摘要

An integrated current-sensing circuit for low-voltage buck regulator is presented. The minimum achievable supply voltage of the proposed current-sensing circuit is 1.2 V implemented in a CMOS technology with V{sub}(TH) = 0.85 V, and the current-sensing accuracy is higher than 94%. With the developed current-sensing circuit, a buck regulator, which is able to operate at a 1.2-V supply, is implemented. A maximum output current of 120 mA and power-conversion efficiency higher than 89% are achieved.