An AM-PM Compensation of Differential Power Amplifier using Capacitance Neutralization

This paper presents an AM-PM compensation of a differential power amplifier using capacitance neutralization. Gain of power amplifier is enhanced by capacitor neutralization technique[1], [2]. The AM-PM of differential power amplifier is compensated by neutralization technique since it reduces influence by the change of gm against power. The differential power amplifier with cross-coupled capacitors are fabricated with a GaN HEMT. The AM-PM of the fabricated differential power amplifier is reduced by 22 degree compared with a singlephase power amplifier without the cross-coupled capacitance. And it achieves gain of 20 dB and power added efficiency of 35 % with output power of 36 dBm at 17.7GHz.