| 摘要 |
PROBLEM TO BE SOLVED: To improve distortion characteristics and to enhance the efficiency of an amplifier by providing first and second semiconductor amplifying elements and a bias circuit, and linearly changing resistance value on the high potential side of a resistance type potential dividing circuit so that temperature characteristics of idle current at the time of being not inputted from an input terminal become negative characteristics. SOLUTION: In a high frequency power amplifier module (high frequency power amplifier) incorporated with transistors in multiple stages, a resistor 15 on the high potential side of the resistance type potential dividing circuit (bias circuit) to be connected to the control terminal of each transistor is a temperature compensation type resistor to linearly change the resistance value. Therefore, when the temperature rises, the resistance value of the temperature compensation resistor is successively increased, the potential of a control electrode is lowered, and the temperature characteristics of the idle current become negative. The temperature of the resistor on the high potential side of the resistance potential dividing circuit is only compensated by the bias circuit of semiconductor amplifying elements on the first (input) stage and final (output) stage, and it is not necessary to attach any other component for fixing a drain current.
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