| 摘要 |
<P>PROBLEM TO BE SOLVED: To decrease a variation of a phase margin of a series regulator circuit associated with magnitude discrepancy of a load L. <P>SOLUTION: A constant voltage circuit 10 comprises an amplifier element Q1 that is connected between an input voltage and a load and supplies output voltage to the load; a voltage detection unit 4 that outputs a voltage signal being dependent on the output voltage; a differential unit 1 that outputs differential voltage corresponding to a difference between a reference voltage and the voltage signal by a differential pair composed of a pair of transistors Q2 and Q3; an amplifier unit 3 that amplifies the differential voltage and inputs it to a control terminal of the amplifier element Q1; and a load detection unit 5 that detects a magnitude of the load and outputs an instruction signal corresponding to the magnitude of the load. The differential unit 1 comprises a conductance change unit 6 that changes a conductance value of the differential pair according to the instruction signal. <P>COPYRIGHT: (C)2012,JPO&INPIT |
