NCP1378 Datasheet (ON Semiconductor) - PWM Current-Mode Controller

NCP1378, PWM Current-Mode Controller

Pin Symbol Function 1 Demag Core reset detection and OVP 2 FB Sets the peak current setpoint 3 CS Current sense input and skip cycle level selection 4 GND 5 Drv 6 VCC 7 NC 8 HV The IC ground Driving pulses Supplies the IC * High *voltage pin Description The auxiliary FLYBACK

NCP1378 PWM Current- Mode Controller for Free- Running Quasi- Resonant Operation The NCP1378 combines a true current mode modulator and a demagnetization detector to ensure full borderline/critical Conduction Mode in any load/line conditions and minimum drain voltage switching (Quasi- Resonant operation).

Due to its inherent skip cycle capability, the controller enters burst mode as soon as the power demand falls below a predetermined level.

As this happens at low peak current, no audible noise

NCP1378 Features

* an efficient protective circuitry that, in presence of an overcurrent condition, disables the output pulses and enters a safe burst mode, trying to restart. Once the default has gone, the device auto- recovers. Finally an internal 1.0 ms Soft- Start eliminates the traditional startup stress. The NCP