Multiple output converter having a single transformer winding and independent output regulation

摘要

A DC-DC converter includes a transformer having a primary winding and a secondary winding. The secondary winding includes first and second terminals. An input circuit is connected to the primary winding for coupling an input DC voltage to the primary winding. A first output channel is connected to the first terminal of the secondary winding, and is connected to a first output. The first channel includes a first switch connected in series with a first inductor. A second output channel is connected to the second terminal of the secondary winding, and is connected to a second output. A first and a second capacitor connect the first and second outputs to a return lead. A second switch connects the first output channel to the return lead. A third switch connects the second output channel to the return lead. A pulse width modulator is connected between one of the outputs to drive the input circuit. A pulse width modulator is connected between the first output and the first switch for regulating the duty ratio of the first output channel independently of the second output channel.