ZHCSBB1D July 2013 – March 2018 UCC28740
The UCC28740 is a flyback controller that provides constant-voltage (CV) mode control and constant current (CC) mode control for precise output regulation. While in CV operating range, the controller uses an opto-coupler for tight voltage regulation and improved transient response to large load steps. Accurate regulation while in CC mode is provided by primary side control. The UCC28740 uses frequency modulation, peak primary current modulation, valley switching and valley hopping in its control algorithm in order to maximize efficiency over the entire operating range.