High-Efficiency CMOS Power Amplifier Using Uneven Bias for Wireless LAN Application

ETRI Journal

关键词: 80211g WLAN;    high efficiency;    current mode transformer;    CMOS power amplifier;    Balun transformer;   

Others  :  1186185
DOI  :  10.4218/etrij.12.1812.0024

【 摘 要 】

This paper proposes a high-efficiency power amplifier (PA) with uneven bias. The proposed amplifier consists of a driver amplifier, power stages of the main amplifier with class AB bias, and an auxiliary amplifier with class C bias. Unlike other CMOS PAs, the amplifier adopts a current-mode transformer-based combiner to reduce the output stage loss and size. As a result, the amplifier can improve the efficiency and reduce the quiescent current. The fully integrated CMOS PA is implemented using the commercial Taiwan Semiconductor Manufacturing Company 0.18-μm RF-CMOS process with a supply voltage of 3.3 V. The measured gain, P_1dB, and efficiency at P_1dB are 29 dB, 28.1 dBm, and 37.9%, respectively. When the PA is tested with 54 Mbps of an 802.11g WLAN orthogonal frequency division multiplexing signal, a 25-dB error vector magnitude compliant output power of 22 dBm and a 21.5% efficiency can be obtained.

   

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