Power chip

The NCP1365 offers a novel approach to output power levels of a few watts above 20 W in general power supply flyback applications. Thanks to a new approach, this new controller eliminates the need for an auxiliary feedback circuit (typically an optocoupler and TL431 reference) while achieving excellent line and load regulation. The NCP1365 operates in a valley-lock quasi-resonant peak current control mode at high loads to provide high energy efficiency. When auxiliary side power starts to disappear, the controller will automatically adjust the duty cycle, then at lower loads, the controller goes into pulse frequency modulation with a fixed peak current via valley switching survey. This technique allows output regulation to be maintained under small dummy loads. Valley lockout in the first 4 valleys prevents valley skipping operation, then solid switching at lower loads provides high energy efficiency.