| 摘要 |
Provided is a variable gain circuit in which it is not necessary to provide a plurality of phase compensation capacities while stability of a circuit is maintained regardless of a set variable gain. A variable gain circuit comprises a precedent stage amplifier circuit for amplifying an external input signal, a subsequent stage amplifier circuit for amplifying an output signal of the precedent stage amplifier circuit, a phase compensation circuit having a fixed capacitative element and connected between an output terminal and an input terminal of the subsequent stage amplifier circuit, and a gain setting circuit adapted to be capable of setting a gain value of the whole of the precedent stage amplifier circuit and the subsequent stage amplifier circuit to a plurality of values, wherein one of the gain value and a transconductance value of the precedent stage amplifier circuit can be set in conjunction with the other.
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