Fairchild SG6742 Manuals

This application note introduces the design guidelines for the FAN6754A PWM controller, which features green mode, frequency hopping, constant power limit, and various protection functions. The power supply can meet stringent standby power regulations by maximizing light-load efficiency, and frequency hopping reduces electromagnetic emission. The constant-power-limit function minimizes component stress in abnormal conditions, and integrated protection functions improve reliability without increasing system cost. This application note explains how to replace the SG6742 PWM controller with the FAN6754A and provides a summary of the differences between the two devices.

FAN6754 is a PWM controller introduced by Fairchild company. It has green mode, frequency hopping, constant power limit and other functions, which can meet stringent standby power regulations. This application note explains how to use FAN6754 to replace SG6742. Although the pin configuration of the two devices is the same, FAN6754 has higher efficiency and better performance, so some external components need to be replaced when replaced.

This application note describes a detailed design strategy for a high-efficiency, compact flyback converter. Design considerations, mathematical equations, and guidelines for a Printed-Circuit-Board (PCB) layout are presented.