NCP1248

NCP1248 Fixed Frequency Current Mode Controller for Flyback Converters The NCP1248 is a new fixed-frequency current-mode controller featuring the Dynamic Self-Supply. This function greatly simplifies http://onsemi.com the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during start-up, transients, latch, stand-by etc. This device contains a special HV detector which detect the application unplug from the AC input SOIC−7 line and triggers the X2 discharge current. This HV structure allows CASE 751U the brown-out detection as well. It features a timer-based fault detection that ensures the detection of MARKING DIAGRAM overload and an adjustable compensation to help keep the maximum power independent of the input voltage. Due to frequency foldback, the controller exhibits excellent efficiency in light load condition while still achieving very low standby power consumption. Internal frequency jittering, ramp compensation, and a versatile latch input make this controller an 8 48Axxx ALYWX G 1 excellent candidate for the robust power supply designs. A dedicated Off mode allows to reach the extremely low no load input power consumption via “sleeping” whole device and thus minimize the power consumption of the control circuitry. Features Fixed-Frequency Current-Mode Operation using 65 kHz/100 kHz 48Axxx = Specific Device Code xxx = 065 for 65 kHz = 100 for 100 kHz A = Assembly Location L ...