A 28-GHz CMOS Power Amplifier Linearized by Dynamic Conductance Control and Body Carrier Injection

A 28-GHz linear CMOS cascode power amplifier (PA) that adopts two types of analog linearization methods, dynamic conductance control (DCC) and body carrier injection (BCI), is presented here. The former method controls the load conductance of a common-source (CS) amplifier according to the input power of the PA. This improves the AM-AM and AM-PM characteristics of the cascode PA, which is also analyzed with an equivalent circuit model. The latter injects the carrier signal into the body of a common-gate (CG) transistor, which increases the voltage headroom of the CS transistor. This improves the AM-AM of the cascode PA and also helps to stabilize the PA by reducing the drain-source capacitance of the CG transistor. The proposed PA is fabricated in a 65-nm CMOS process and shows a gain of 15.9 dB, an output 1-dB compression point of 17.7 dBm, and a saturation output power of 19.1 dBm with a peak power-added efficiency (PAE) of 41.2% at 28 GHz.