Patent ID: 6573797
Filing Date: 2003-06-03
Classification: H03F

Abstract:
A high-frequency power amplifier comprising: an amplifying element for amplifying high-frequency power; an input-side matching circuit being provided at an input side of the amplifying element; and an output-side matching circuit being provided at an output side of the amplifying element, whereinthe high-frequency power amplifier has a current absorbing unit which is inserted between the input side of the amplifying element and the input-side matching circuit, and absorbs a current of a higher-harmonic frequency contained in a signal of a fundamental wave with which the amplifying element operates, wherein said current absorbing unit includes an LC-series resonance circuit having a higher-harmonic frequency as a resonance frequency, an inductive reactance (XL) being connected at a connection point between the input side of said amplifying element and said input-side matching circuit and a capacitive reactance (XC) one end of which is connected to the above connection point and the other end of which is grounded, and whereby said LC-series resonance circuit absorbs current of the higher-harmonic frequency flowing into the input side of said amplifying element through a parasitic capacitance from the output side of the amplifying element.