| 摘要 |
An operational amplifier circuit reduces signal distortion in switching circuits resulting from flow of bias current through an analog switch having a resistance that changes with a common mode voltage level. The circuit includes an operational amplifier, and first, second, and third switches monolithically integrated on a same integrated circuit substrate. The first switch is connected in a feedback path of the operational amplifier between an output and an inverting input of the operational amplifier. The second and third switches each have one terminal connected to a non-inverting input of the operational amplifier and another terminal receiving a respective input signal, and operate to provide a selected input signal to the amplifier. The first switch operates in a conducting state before, during, and after any period in which any of the second and third switches is in the conducting state. The switches may be analog switches having same operational characteristics. |
