摘要 |
An output power detecting circuit of transmitter, comprises a signal detecting unit connected between the transmitter output end and the transmitter control unit to detect an output signal of transmitter, a reference voltage generating unit, a differential amplifier having non-inverted input end, inverted input end and output end to supply a detection voltage to the control unit from the output end and a voltage limiting element connected between the inverted input end and reference potential point, wherein the detection voltage output from the signal detecting unit is supplied to the non-inverted input end, the reference voltage output from the reference voltage generating unit and an additional reference voltage of the transmitting level indicating voltage output from the control unit are respectively supplied to the inverted input end, the additional reference voltage supplied to the inverted input end is limited with the voltage limiting element and the detection voltage increasing with increase of the detection voltage is kept within the dynamic range for gain control of the control unit.
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