| 摘要 |
PROBLEM TO BE SOLVED: To supply a more stable output voltage to a load without detecting an output current unlike a conventional way, even if an output of an operational amplifier fluctuates due to a load current. SOLUTION: Two negative feedback resistors R1 and R2 are connected in series between an output of an operational amplifier circuit 10A, and a ground and negative feedback from between them is applied to a differential amplifier 2, and thus, its gain is made to be a value of (1+R1/R2) times. The negative feedback resistors R1 and R2 connected in series to the output terminal of the operational amplifier circuit 10A and the ground are separated from each other, and a negative feedback resistance means is configured so as to include wiring resistors r1 and r2 of return to a portion before a load 4. With this configuration, since a gain is controlled by the differential amplifier 2 for a portion of increasing a voltage fall of wiring resistors r1 and r2 based on an increased portion of a load current and the gain can be increased, a potential variation due to the load current can be reduced, and thus, the stable output voltage by the operational amplifier circuit 10A can be obtained without detecting the output current unlike the conventional way. COPYRIGHT: (C)2007,JPO&INPIT
|
