| 摘要 |
PROBLEM TO BE SOLVED: To eliminate temperature dependence of a gain control feature, such as a gain control voltage by equipping a first voltage current linear conversion part, a first temperature feature compensation part, a second voltage current linear conversion part and a second temperature feature compensation part and controlling a voltage gain, regardless of fluctuation of the absolute temperature in a variable gain cell so that a voltage gain becomes constant. SOLUTION: A gain control circuit 1 of a variable gain amplifier is constituted with a gain control voltage path block 22 and a reference voltage path block 23. The gain control voltage path block 22 and the reference voltage path block 23 each have the same structure, a gain control voltage and a reference voltage are inputted to the voltage current linear conversion part 26, voltage current is converted linearly and outputted, and first and second currents are outputted to a variable gain cell 27 from a temperature characteristic compensating part 12. That is, the variable gain cell 27 is controlled by the gain control circuit 1, and fluctuation of voltage gain by absolute temperature is eliminated.
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