A 31.5dBm outphasing class-D power amplifier in 45nm CMOS with back-off efficiency enhancement by dynamic power control

A transformer-combined fully Integrated outphasing class-D PA In 45nm CMOS achieves 31.5dBm peak output power at 2.4GHz with 27% efficiency, and supports over 86dB of output power range. The PA employs Dynamic Power Control (DPC) whereby sections of the PA are turned on-off dynamically according to the OFDM amplitude to reduce power dissipation at backoff. The PA delivers 24.8dBm average power while meeting 64-QAM WLAN requirements. PAE is 16% when using DPC, which represents a 33% efficiency enhancement compared to the DPC-disabled mode. At lower average power of 20.5dBm, DPC enables a 140% enhancement in average efficiency, hence battery life.

[1]  Asad A. Abidi,et al.  An Outphasing Power Amplifier for a Software-Defined Radio Transmitter , 2008, 2008 IEEE International Solid-State Circuits Conference - Digest of Technical Papers.

[2]  Yorgos Palaskas,et al.  A highly linear 25dBm outphasing power amplifier in 32nm CMOS for WLAN application , 2010, 2010 Proceedings of ESSCIRC.

[3]  K. Soumyanath,et al.  A 28.1dBm class-D outphasing power amplifier in 45nm LP digital CMOS , 2009, 2009 Symposium on VLSI Circuits.

[4]  A.M. Niknejad,et al.  A Fully Integrated Dual-Mode Highly Linear 2.4 GHz CMOS Power Amplifier for 4G WiMax Applications , 2009, IEEE Journal of Solid-State Circuits.

[5]  C.G. Sodini,et al.  A 5.8GHz, 47% efficiency, linear outphase power amplifier with fully integrated power combiner , 2006, IEEE Radio Frequency Integrated Circuits (RFIC) Symposium, 2006.

[6]  Gang Liu,et al.  Fully Integrated CMOS Power Amplifier With Efficiency Enhancement at Power Back-Off , 2008, IEEE Journal of Solid-State Circuits.

[7]  A.A. Abidi,et al.  All-Digital Outphasing Modulator for a Software-Defined Transmitter , 2009, IEEE Journal of Solid-State Circuits.

[8]  Lawrence E. Larson,et al.  A 65nm CMOS 2.4GHz 31.5dBm power amplifier with a distributed LC power-combining network and improved linearization for WLAN applications , 2010, 2010 IEEE International Solid-State Circuits Conference - (ISSCC).

[9]  Debopriyo Chowdhury,et al.  A 90nm CMOS power amplifier for 802.16e (WiMAX) applications , 2009, 2009 IEEE Radio Frequency Integrated Circuits Symposium.