Barnes & Thornburg
Dual input voltage power source for selectively switching between voltage doubler rectification and full-wave rectification functions
 In an automatic voltage switching power source having a full-wave rectifier circuit and a voltage doubler circuit, a controller comprises a plurality of voltage level detectors which are associated with an input ac voltage and detect different voltages, and a switching signal generator which generates a delayed signal for switching between the full-wave rectifier and voltage doubler circuits based on the logical product of the outputs of the voltage level detectors, thereby preventing the electric circuit of the power source and the electric device to be supplied with the power from being damaged by excessively high voltages. 
Fuji Electrochemical Co., Ltd.
H B
H02M B23H
inventional inventional
Fumiaki Noboru
Nakao Kato