| 摘要 |
PROBLEM TO BE SOLVED: To drop terminal voltage of an output capacitor linearly to ground potential always in a fixed time in a voltage source circuit using the output capacitor. SOLUTION: A constant current circuit having characteristic fluctuation correlative to the characteristic fluctuation of a reference voltage source 1 is composed of a second voltage source 2 and a third voltage source 3 having the same characteristics as the reference voltage source 1 giving an initial voltage value to the output capacitor C1; magnification circuits 4, 5; a reference resistance R1; a transistor Q1 supplied with a driving current from the second voltage source 2; and an operational amplifier OP1 controlling the driving current of the transistor Q1. The same transistor Q2 as the transistor Q1 is connected in parallel with the output capacitor C1, and the output capacitor C1 is discharged at a current value correlative to the current value flowing in the constant current circuit. COPYRIGHT: (C)2008,JPO&INPIT
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