NCP1234 - Fixed Frequency Current Mode Controller
Pin No Pin Name Function 1 LATCH Latch *Off Input 2 FB 3 CS Feedback Current Sense 4 GND 5 DRV 6 VCC Drive output 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 the direct connec
NCP1234 Fixed Frequency Current Mode Controller for Flyback Converters The NCP1234 is a new fixed frequency current mode controller featuring Dynamic Self Supply (DSS).
This device is pin to pin www.onsemi.com compatible with the previous NCP12xx families.
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 fr
NCP1234 Features
* a timer
* based fault detection that ensures the detection of overload independently of an auxiliary winding, and an adjustable compensation to help keep the maximum power independent of the input voltage. Finally, due to a careful design, the precision of critical parameters is well controlle