| 摘要 |
PROBLEM TO BE SOLVED: To improve the linearity characteristic of the gain of a gain control amplifier in a semiconductor integrated circuit for communication provided with a high frequency power amplifier circuit including the gain control amplifier and a bias circuit for supplying a bias current to linearly change the gain of the gain control amplifier and to provide a wireless communication apparatus employing the same. SOLUTION: A bias generating circuit for supplying a bias current to a liner amplifier being a component of the high frequency power amplifier circuit for communications comprises a plurality of variable current sources whose currents and whose start levels differ from each other. The variable current sources are controlled with an input control voltage to compose the currents, the composite current is used for a bias current, and the composite current is exponentially changed with respect to the input control voltage. COPYRIGHT: (C)2003,JPO
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