onsemi (Ansemi)

SOIC-7

taping

2500

The NCP12400 is a new fixed-frequency current-mode controller with dynamic self-power capability. This feature activates the internal start-up current source to power the controller during start-up, transients, latch-up, standby, etc., greatly simplifying the design of auxiliary power supplies and VCC capacitors. The device contains a special high voltage detector that detects the application of unplugging from the AC line and triggers the X2 discharge current. This high voltage structure also enables undervoltage detection. It features timer-based fault detection to ensure overload detection and adjustable compensation to help maintain maximum power regardless of input voltage. Due to frequency foldback, the controller has excellent energy efficiency at light load conditions while achieving very low standby power consumption. Internal frequency jittering, slope compensation, and a multifunction latch input make this controller an excellent candidate for rugged power supply designs. A dedicated shutdown mode achieves extremely low no-load input power consumption by putting the entire device to "sleep", thereby minimizing power consumption in the control circuitry. Additionally, the NCP12400 features a quiet skip mode that locks the skip frequency below the audible range. This feature achieves reduced noise caused by switching pulses in skip mode.