Power chip

The NCP1071 integrates a fixed frequency current mode controller and 700 V MOSFETs. Using PDIP-7 or SOT-223 encapsulation, the NCP1071 offers a high level of integration including soft-start, frequency dithering, short-circuit protection, cycle skipping, maximum peak current set point, slope compensation, and dynamic self-power supply (no auxiliary winding required) . Unlike other monolithic solutions, the NCP1071 is noiseless: during normal load operation, it switches at one of the available frequencies (65, 100, 130 kHz). When the demand for output power disappears, the IC will automatically enter frequency foldback mode, providing excellent energy efficiency at light loads. When power demand decreases further, it enters skip mode, reducing standby power consumption to no-load conditions. Protection features include: timers to detect overload or short circuit events, overvoltage protection with automatic recovery, and AC input line voltage detection. To improve standby performance, connecting an auxiliary winding stops DSS operation, helping to reduce input power consumption on the high line to less than 50 mW.

UCC2809-1 Economical Primary Side Controller