| 摘要 |
<P>PROBLEM TO BE SOLVED: To attain a capacitor input type full-wave rectifier circuit only with n-channel MOSFETs. <P>SOLUTION: A resistor 101 is connected to the source sides of MOSFETs 22, 24, constitutes a current detection circuit which detects current flowing in the MOSFETs 22, 24, and outputs voltage corresponding to a current value to an inverted input terminal of a comparator 104. The comparator 104 compares a voltage which becomes a predetermined threshold to be set by predetermined division ratio of resistors 102, 103 with the voltage of the resistor 101, when it is regarded that the voltage of the resistor 101 becomes smaller than the predetermined threshold, and the current flowing in the resistor 101 becomes smaller than the predetermined threshold, prevents backflow of the current by a smooth capacitor 81 by turning transistors 105, 106 on to control the MOSFETs 22, 24 off. This technology is applicable to a capacitor input type full-wave rectifier circuit. <P>COPYRIGHT: (C)2013,JPO&INPIT |
