| 摘要 |
PURPOSE:To attain a stable loop switching without causing switching noise or mutual interruption between loops at the switching by using a switching circuit to short-circuit or open inverting and noninverting input terminals of 1st and 2nd operational amplifiers. CONSTITUTION:Switches 11a, 11b composed of analog switches are connected between the inverting and noninverting input terminals of the 1st and 2nd operational amplifiers 10a, 10b via a resistor R2 respectively. When a switching control signal SS is inputted, the switches 11a, 11b are opened, closed respectively and an output voltage PS or inverse of the output voltage PS' are fed to the operational amplifier 10a and its difference voltage E is outputted. Then the inverting and noninverting input terminals of the operational amplifier 10b are short-circuited by the switch 11b. Thus, no switching noise nor mutual interruption between loops is caused at the moment of loop switching. |
