In switched-mode power supplies the problem of stabilizing two or more output voltages often arises. Since with pulse-width modulation of the switching power transistors only one output can be exactly regulated it is necessary to restabilize the other outputs with additional regulators. For this particular case, transductors have been developed with an efficiency of over 90 % at operating frequencies between 20 kHz and 50 kHz. They can be used in push-pull and forward converters.