Patent ID: 8963631
Filing Date: 2015-02-24
Classification: H03F

Abstract:
1. A signal amplifying circuit of a communication device, comprising: an amplifier, comprising a first input terminal, a second input terminal, and an output terminal, wherein the first input terminal is coupled with a fixed-voltage terminal; a feedback circuit, coupled with the second input terminal and the output terminal of the amplifier; a digital-to-analog converter (DAC); a signal processing circuit; a switch, configured to selectively couple the second input terminal of the amplifier with the digital-to-analog converter or the signal processing circuit; and a control unit coupled with the switch and configured to control the operation of the switch, wherein the output terminal of the amplifier is utilized for coupling with a transmission channel or a measuring circuit and for outputting a transmission signal to the transmission channel when the switch couples the second input terminal of the amplifier with the digital-to-analog converter and the output terminal of the amplifier is coupled with the transmission channel, and the measuring circuit is allowed to measure at least one parameter of the signal processing circuit through the output terminal of the amplifier when the switch couples the second input terminal of the amplifier with the signal processing circuit and the output terminal of the amplifier is coupled with the measuring circuit.