HIGH FREQUENCY POWER AMPLIFIER CIRCUIT

摘要

PROBLEM TO BE SOLVED: To provide an inexpensive high frequency power amplifier circuit incorporating a bias control circuit whereby stable output power can be obtained by decreasing the number of adjustment resistors to correct deviation in bias voltage due to the manufacturing dispersion of components configuring the high frequency power amplifier circuit so as to reduce the chip size and the time required for adjustment of the resistors. SOLUTION: A high frequency power amplifier circuit (210) for providing a prescribed bias to power amplifier transistors (211 to 213) to set the output power includes: a bias supply circuit (231) capable of supplying a plurality of bias voltages or bias currents to each amplifier stage; and a bias selection means (232) for selecting one of the bias voltages or bias currents outputted from the bias supply circuit and supplying the selected voltage or current to a corresponding power amplifier transistor; and a bias selection control circuit (233) provided with the adjustment resistors and generating a signal to control the bias selection means. A bias control circuit (230) is configured so that the bias voltage applied to the control terminal of the power amplifier transistors can be controlled by the resistance of the adjustment resistors in accordance with the manufacturing dispersion of the components. COPYRIGHT: (C)2005,JPO&NCIPI