A Fully Integrated High Efficiency 2.4 GHz CMOS Power Amplifier with Mode Switching Scheme for WLAN Applications

Abstract

A 3.3 V mode-switching RF CMOS power amplifier (PA) for WLAN applications is presented, which is integrated into a 55-nm bulk CMOS process. The proposed PA offers both static control and dynamic power control, allowing it to operate efficiently in both low-power and high-power modes. The pure low-power mode is achieved by reducing power cells, which are also used for linearization in high power mode. The low-power mode is achieved by reducing the number of power cells which are also used for linearization in the high-power mode. In the dynamic power control mode, the total AM–AM and AM–PM distortion is effectively compensated for by dynamically controlling the number of power cells and adjusting the matching input. The proposed PA achieves an output P1dB of 27.6 dBm with a PAE of 32.7% and an output P1dB of 17.7 dBm with a PAE of 10% in high-power and low-power modes, respectively. It is measured with an 802.11 n 64-quadrature-amplitude-modulation (MCS7) signal and shows a maximum average power of 19 dBm under an error-vector-magnitude (EVM) of −27 dB.