| 摘要 |
PROBLEM TO BE SOLVED: To provide a semiconductor integrated circuit for high-frequency power amplifier capable of highly accurately performing feedback control of output power by improving detection sensitivity of an output power detecting circuit, in a region where an output level is low in a radio communication system for detecting an output level to perform feedback control of the output power, and to provide an electronic component (power module) for high-frequency power amplification. SOLUTION: The output power detecting circuit (220) is provided on a poststage of a power amplifier unit (210) for amplifying a high-frequency transmission signal, detects an output level required for feedback control of the output power, and is configured by two detecting circuits each capable of detecting an output signal. A second detection circuit (222) is configured so as to perform detecting operation using the output of a first detection circuit (221) as a bias. The first detection circuit is configured so that it has higher detection sensitivity in a region where the output level is low than that of the second detection circuit, and so that the output of the first detection circuit is saturated at earlier time point than that of the second detection circuit when it is controlled to gradually increase the output level. COPYRIGHT: (C)2006,JPO&NCIPI
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