NCP1238 Datasheet (ON Semiconductor) - Fixed-Frequency Controller

NCP1238, Fixed-Frequency Controller

Pin No Pin Name Function 1 LATCH Latch *off Input 2 FB Feedback 3 CS Current Sense 4 GND * 5 DRV Drive Output 6 VCC VCC Input 8 HV High *Voltage Pin Pin Description Pull the pin up or down to latch *off the controller.

An internal current source allows

NCP1238 Fixed Frequency Current Mode Controller for Flyback Converters The NCP1238 is a new generation of the NCP12xx fixed frequency current mode controllers featuring Dynamic Self Supply (DSS), pin to pin compatible with the previous generation.

The DSS function greatly simplifies the design of the auxiliary supply and the VCC capacitor by activating the internal startup current source to supply the controller during transients.

Due to its proprietary

NCP1238 Features

* Timer

* Based Overload Protections with Auto

* Recovery (Option B) or Latched (Option A) Operation

* High

* Voltage Current Source with DSS with Built

* in Brown

* out and Line Overvoltage Protections

* Fixed

* Frequency Current