| 摘要 |
A direct-voltage converter for supplying an appliance with an inductive component, in which two transistors are connected in series between direct-current voltage terminals and are made alternatively conductive in a push-pull mode by the first of two windings of a transformer. Two free-running diodes are connected in parallel to the transistors, and a junction between the two diodes supplies their output voltage. This junction is connected to a further junction between the transistors, through a third winding on the transformer. An electronic switch is connected in parallel with a fourth winding of the transformer, and is periodically made conductive by the output voltage through a pulse shaper with a switching pulse. The pulse shaper has two direct current circuit points which determine the peak value and relationship of currents flowing through the two transistors. An amplitude-comparison stage in the pulse shaper has inputs connected to the two circuit points. The output voltage of the amplitude-comparison stage controls the frequency of the switching pulse. The arrangement is such that the converter protects against overload.
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