Power Supply with Pulse Width Modulation Through Opto Couplers
Original Publication Date: 1980-Aug-01
Included in the Prior Art Database: 2005-Feb-13
The switched power supply shown in Fig. 1A comprises three main parts. Control part 1, supplied locally with voltage VL from a regulator fed from +/- VIN, provides time reference and initial pulses to the output (start phase). Output part 2 comprises two Darlington power devices T1 and T2 which drive the output transformer primary N1. The secondary is made up of two windings, the main one N2 that supplies the regulated output voltage to the load and the auxiliary one N3 which provides a voltage +Vx, referenced to load ground. Regulating part 3 is used for pulse-width modulation control of the power supply.