Patent ID: 8456155

Claim:
A radio-frequency power amplifier comprising: an input matching circuit including at least one inductor, the input matching circuit receiving an input signal and matching input impedances with each other; an amplifier amplifying the input signal that is passed through the input matching circuit; and a test circuit, wherein the test circuit comprises: a capacitor configured to be connected to the inductor in the input matching circuit through a first test switch; a negative resistance transistor provided between the inductor and a first voltage source terminal with a second test switch being interposed between the inductor and the negative resistance transistor; and a current source transistor provided between a second voltage source terminal and the inductor, and wherein, in testing, the first and second test switches and the current source transistor are turned on to cause the inductor and the test circuit to form a radio-frequency oscillator and, in normal operation, the first and second test switches and the current source transistor are turned off.