摘要 |
Tank circuitry coupled to the output terminals of a differential power amplifier includes two trap circuits configured to divert harmonic signals away from the output terminals. A tank inductor is provided to form a tank circuit in conjunction with each one of the trap circuits. At certain harmonic frequencies of the input signal to the differential power amplifier, the trap circuits are resonant and present a substantially low impedance path to ground, thereby diverting harmonic signals away from the output terminals of the differential power amplifier. At the fundamental frequency of the input signal to the differential power amplifier, the trap circuits are resonant with the tank inductor and present a substantially high impedance compared to the load impedance presented at the output terminals of the differential power amplifier, thereby reducing the loading effect of the trap circuits at the fundamental frequency. |