Patent ID: 7768354

Claim:
A radio-frequency power amplifier comprising: a first transistor operable to amplify a power of a radio-frequency signal; and a bias circuit operable to supply a bias current to the first transistor; the bias circuit including: a second transistor that has a collector terminal connected to a first power supply; a first resistance element that has one end connected to an emitter terminal of the second transistor and has the other end connected to a base terminal of the first transistor; a second resistance element that has one end connected to the emitter terminal of the second transistor and has the other end connected to ground potential; at least one third resistance element provided between a base terminal of the second transistor and a second power supply; and a plurality of temperature compensation circuits connected to the base terminal of the second transistor and operable to control a base potential of the second transistor so that the potential falls as a temperature rises, at least one of the plurality of temperature compensation circuits being unlike all the rest of the plurality of temperature compensation circuits in configuration.