The FA531X series are bipolar ICs for switching power supply control that can drive a power MOSFET. These ICs contain many functions in a small 8-pin package. With these ICs, a high-performance and compact power supply can be created because not many external discrete components are needed. n Features • Drive circuit for connecting a power MOSFET • Wide operating frequency range (5 to 600kHz) • Pulse-by-pulse overcurrent limiting function • Overload cutoff function (Latch or non-protection mode selectable) • Output ON/OFF control function by external signal • Overvoltage cutoff function in latch mode • Undervoltage malfunction prevention function • Low standby current (90mA typical) • Exclusive choices by circuits (See selection guide on page 25) • 8-pin package (DIP/SOP) n Applications • Switching power supply for general equipmen