Patent ID: 9660591
Date: 2017-05-23
CPC Classifications: H03F

Claim:
1. A power amplifier comprising: a power splitter that splits a first signal into a second signal and a third signal delayed from the second signal by about 90 degrees, wherein the power splitter includes a coupled-line 3 dB coupler; a first amplifier that outputs a fourth signal by amplifying the second signal when a power level of the first signal equals or exceeds a first level; a second amplifier that outputs a fifth signal by amplifying the third signal when the power level of the first signal equals or exceeds a second level higher than the first level; a first phase shifter that receives an input of the fourth signal and outputs a sixth signal delayed from the fourth signal by about 45 degrees; a second phase shifter that receives an input of the fifth signal and outputs a seventh signal advanced from the fifth signal by about 45 degrees; and a combining unit that outputs an amplified signal of the first signal by combining the sixth signal and the seventh signal, wherein the power splitter, the first amplifier, the second amplifier, the first phase shifter, the second phase shifter, and the combining unit are provided on a single IC chip.