A Sub-1 GHz +24 dBm Linear Two-Stage Power Amplifier with Self-Adaptive Bias Control

A Sub-1 GHz two-stage linear CMOS power amplifier (PA) for OFDM IoT application in 180nm CMOS technology is presented. In order to improve the linearity, it employs the self-adaptive bias (SAB) control technology in which the bias of PA could be changed linearly with the amplitude of the input signal. Compared with the PA with FB (fixed bias) control, it improves the linearity of high-power output signal significantly. Post-simulation results show that its P1dB is 24.06dBm, which is 2.98dBm higher than that of the PA with FB, and the PAE is 18.85%@17dBm. The total current consumption is 80.3mA@17dBm from a 3.3V supply voltage and the core size is 0.227mm2.