Maxim Integrated Products, Inc.
High efficiency buck-boost systems and methods

Abstract:

Various embodiments of the invention provide for a buck-boost circuit that is immune against being stuck in an undesirable mode of operation. The circuit does not require any additional intermediate states other than buck-mode and boost-mode when managing transitions between buck and boost mode. In certain embodiments, a robust and simple buck-boost topology ensures efficient and rapid transitions by operating comparators that are coupled to switching elements of the buck-boost in such a manner that the inductor current can be selectively monitored to detect an inductor current slope during a power transfer phase. Information about the current slope enables a controller to make a decision whether a transition to another state is appropriate.