| 摘要 |
PROBLEM TO BE SOLVED: To provides an electronic component for high frequency power amplification (power module) capable of improving detection sensitivity of an output power detection circuit for a low output level region and conducting a highly precise feedback control, as for a wireless communication system in which an output level is detected, and gain of a variable gain amplifier at a prestage of a power amplifier is controlled, and feedback control is performed so that the magnitude of a transmit signal of high frequency inputted into the power amplifier is changed to be set to a desired output level. SOLUTION: An output power detecting circuit (20) is provided at a poststage of a power amplifier for amplifying a transmit signal of high frequency, and performs detection of an output level required for feedback control of an output power. The output power detecting circuit (20) comprises a first detecting circuit (21) for detecting the output level and outputting current proportional to an input, and a second detector (22) for detecting the output level and outputting current of square root conversion of the input. The output power detecting circuit (20) synthesizes the output of these detecting circuit and outputs it as a detected signal. COPYRIGHT: (C)2006,JPO&NCIPI
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