A dc voltage supply circuit

摘要

A circuit is provided for rectifying an AC input voltage to provide a substantially constant DC output voltage. A composite input voltage is derived from the AC input voltage, which is composed of a scaled input AC voltage shifted by a selected DC bias voltage such that the entire range of such input signal voltages is contained within the supply voltages of detection circuitry which controls the rectifier circuitry. The detection is thus carried out during both the upper and lower excursions of the input AC voltage.