High frequency power amplifier system and wireless communication system

摘要

Disclosed herein is a high frequency power amplifier system having a transistor comprised of a first electrode, a second electrode and a control electrode and for controlling current which flows between the first electrode and the second electrode by applying a potential to the control electrode, and a resistance type potential divider circuit for determining a dc bias potential applied to the control electrode of the transistor, and wherein an input signal is inputted to the control electrode, an output signal is outputted from the first electrode and a control signal is inputted to the resistance type potential divider circuit. One resistor of the resistance type potential divider circuit is comprised of a temperature compensating resistor whose resistance value varies linearly, so that a temperature characteristic of an idle current defined as an output when the control signal is not inputted, assumes a negative temperature characteristic.