Monolithic Power Systems, Inc.
INTEGRATED CIRCUIT OF A BUCK-BOOST CONVERTER WITH OUTPUT CURRENT SENSING FUNCTION

Abstract:

An integrated circuit of a buck-boost converter working in a buck mode with a buck power switching cycle, a boost mode with a boost power switching cycle or a buck-boost mode with a buck-boost power switching cycle. The integrated circuit integrates a first power switch, a second power switch, a third power switch and a fourth power switch, and an output current sensing circuit. The buck-boost power switching cycle consists of a first buck-boost phase, a second buck-boost phase and a third buck-boost phase. The output current sensing circuit samples the current flowing through the first power switch during the second buck-boost phase and the current flowing through the fourth power switch during the third buck-boost phase so as to generate the output current information.