onsemi (Ansemi)

PDIP-8

Tube

50

The products NCP1075A and NCP1075B integrate a fixed frequency current mode controller and 700 V MOSFET. Using the very common PDIP 7 encapsulation, with two different pin outputs, provides a high level of integration, including soft start, frequency jitter, short circuit protection, skip cycle, maximum peak current set point, slope compensation and dynamic self-power supply (DSS, no auxiliary winding required). Unlike other monolithic solutions, the NCP1075A and NCP1075B are noiseless: during normal load operation, when switching at one of the available frequencies (65 or 100 kHz). When the demand for output power disappears, the IC automatically enters frequency foldback mode, providing excellent 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. AC input line voltage detection prevents severe runaway under low input voltage conditions (brownout) as well as over high input line (AC line overvoltage protection). This also enables the overpower protection to compensate for any internal delays at high input voltage conditions, optimizing the maximum output current capability. 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.