Insulating-type switching electric power source device

摘要

An insulating-type switching electric power source device has an input voltage Vin of a primary side that is converted at an input/output ratio determined by switching operations of a switching device, and then is output. Voltage subjected to rectifying and smoothing by a primary-side rectification smoothing circuit is used as detecting signals of the output voltage, to control the time ratio of the switching device. A load regulation correcting circuit outputs load regulation correcting signals correlated with the amount of output current. A temperature compensating circuit corrects the load regulation correcting signals according to the ambient temperature. The load regulation correcting signals correct the output voltage detecting signals according to the fluctuations of the output voltage according to fluctuations in the output current and fluctuations in the ambient temperature. As a result, fluctuations in the output voltage caused by fluctuations in the output current and fluctuations in the ambient temperature are compensated for.