Patent ID: 9143097
Filing Date: 2015-09-22
Classification: H03F,H04B

Abstract:
1. A RF power amplifier comprising: a first band RF amplifier circuit to amplify a first frequency band; a second band RF amplifier circuit to amplify a second frequency band; and a second band power detection circuit, wherein, when an RF input signal having the second frequency band is supplied to an input terminal of the second band RF amplifier circuit, the second band RF amplifier circuit subjects the RF input signal to power amplification and generates an RF amplifier output signal having the second frequency band from an output terminal of the second band RF amplifier circuit, wherein an input terminal of the second band power detection circuit is coupled to the output terminal of the second band RF amplifier circuit, wherein the second band power detection circuit detects a harmonic component that is a whole number multiple of a fundamental wave component of the RF amplifier output signal, and, in accordance with the detected harmonic component, generates, at an output terminal thereof, a detected signal indicative of the signal level of the fundamental wave component of the RF amplifier output signal, and wherein the second band power detection circuit includes an input circuit, which detects the harmonic component, and the input circuit also functions as a harmonic termination circuit that is formed by series-coupling a first inductor to a first capacitor, which is coupled between a ground potential and the output terminal of the second band RF amplifier circuit.