5.25 GHz linear CMOS power amplifier with a diode-connected NMOS bias circuit

In this paper, a 5.25GHz linear CMOS power amplifier (PA) with an integrated diode is presented. The proposed technique improves the linearity of the power amplifier by a diode-connected NMOS transistor. The NMOS diode is effective to suppress both the AM-AM distortion and AM-PM distortion. To verify this concept, the power amplifier is simulated with TSMC 0.13-μm CMOS process. With a power supply of 3.3 V, the proposed power amplifier exhibits a maximum IMD improvement of 25 dB with a PAE of 38.2 % at an output P1dB of 19.6 dBm.