A universal power supply integrated circuit for TV and monitor applications

A switching mode power supply circuit which operates according to the master-slave concept and is located in the primary side of a TV set or monitor offline flyback power supply is described. The circuit ensures the starting function, the standby function according to the primary regulation principle, and the normal operating mode in association with a switching regulator located in the secondary side of the power supply. The circuit provides the base drive of the power switch without external boosters. It ensures various safety functions, such as power transistor current limitation and under- or overvoltage detection. Although mainly designed for the master-slave concept, the circuit can also be used alone, according to the primary regulation concept, or in association with an optocoupler. The circuit layout is presented