| 摘要 |
In a differential pair control type variable gain amplifier, amount of driving current of a current source (30; 30b-30n) is adjusted in accordance with the gain thereof. Specifically, in accordance with a control voltage (VCR) generated by a variable voltage source (25) determining the gain of a differential stage (20, 21) generating an output signal in accordance with an input signal, the amount of driving current of a current source transistor (Q2) of the differential stage is adjusted to be smaller as the gain becomes lower. Only the current in accordance with the gain is consumed, and the current consumption is reduced without causing signal distortion.
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