| 摘要 |
PROBLEM TO BE SOLVED: To inhibit variations of an output voltage by an element manufacture dispersion and a temperature change. SOLUTION: A differential input circuit 101 inputs an AC signal, and superposingly outputs a differential current to a constant current I0. A current subtraction circuit 102 subtracts a constant current from a current subjected to current mirror from a differential input circuit, and outputs the differential current. A current addition circuit 103 adds two differential currents where phases subjected to current mirror from the current subtraction circuit differ by 180 degrees, and hence obtains a fully rectified output current. A resistor R1 is inserted between drains of differential input transistors Tr1, Tr2 in the differential input circuit 101, and a value of current flowing in the differential input transistor is determined by R1. The relative precision between a resistor for converting the output current to voltage and the resistor R1 is secured, and hence variations in the output voltage are suppressed. COPYRIGHT: (C)2011,JPO&INPIT
|
