| 摘要 |
PURPOSE:To miniaturize a drive circuit and speeds up switching by turning on/off push/pull drive of a drive circuit where a part to be driven is subjected to push/pull drive with a relatively large amount of current by an analog switch IC. CONSTITUTION:When an analog switch IC11 is switched to a contact A side, a second operational amplifier (OP) 4 for driving is used as a non-inverted equal-scale type amplifier and an output voltage V2 which is in phase with and has the same amplitude as an output voltage V1 of a first operational amplifier (OP) 2 for driving is output from the output terminal, thus eliminating voltage difference between the output terminals of the OPs 2 and 4 and preventing push-pull drive of a movable part 3. On the other hand, when the IC 11 is switched to the side of a contact B, 0P4 is used as an inverted equal- scale type amplifier and then the output voltage V2 which is out of phase and the same amplitude and the output voltage V1 of the OP 2 are output from the output terminal, thus feeding a drive current corresponding to the potential difference between the output voltages V1 and V2 to the drive coil of the movable part 3. |
