| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a high frequency amplifier circuit capable of suppressing a gain change due to temperature fluctuations while ensuring a low noise characteristic and a high saturation characteristic without mounting a step type variable attenuator. <P>SOLUTION: The high frequency amplifier circuit includes: a variable attenuator that attenuates a high frequency signal; a band gap reference current source circuit that outputs a temperature proportional current and a temperature fixed current on the basis of a semiconductor band gap; and a variable attenuator control voltage formation circuit that outputs a voltage changing at a predetermined inclination to temperatures with the temperature proportional current and the temperature fixed current as an input. Thus, an attenuation amount of the variable attenuator is controlled by an output voltage of the variable attenuator control voltage formation circuit. <P>COPYRIGHT: (C)2013,JPO&INPIT |
