Onsemi NCP1345 quasi-resonant flyback controller

     The onsemi NCP1345 Quasi-resonant Flyback controller is a highly integrated device designed for high-performance offline USB-PD and USB Type-C power converters. The NCP1345 uses a double-pin VCC architecture, which can be directly connected to the auxiliary windings. Simplified VCC management enables a smaller number of components and higher performance.

     The onsemi NCP1345 quasi-resonant flyback controller features an accurate, primary side-based output current limiting circuit that enables constant output current limiting regardless of the programmed output voltage or nameplate output power.

     The NCP1345 features a variety of key protection options, including internal power failure detection, maximum output current limitation independent of input voltage, and latching overvoltage and NTC-ready overheat protection via dedicated pins. In addition, line removal detection enables safe discharge of X2 capacitors during line removal, thus achieving converter durability.