A 20.5 dBm Outphasing Class-F PA with Chireix Architecture at 3.5 GHz for RF Transmitter Front-end

Abstract

An outphasing class-F power amplifier (PA) with Chireix architecture is presented in Global Foundry (GF) 0.13μm Complementary Metal Oxide Semiconductor (CMOS) technology. The proposed circuit is composed of two branch class-F PA and Chireix power combiner with a floating load. The designed outphasing amplifier can provide 20.5 dBm output power from 1.8 V power supply at 3.5 GHz with 52.9 % power added efficiency (PAE). Wideband Code Division Multiple Access (W-CDMA) signal is implemented as input signal to simulate ACPR and the adjacent channel leakage ratios (ACLRs) at 5 MHz are -20.5 dBc/-20.7dBc. After DPD (Digital Pre-Distortion) ACLRs can achieve -44.5 dBc/-44.7dBc at 5 MHz. Furthermore, the chip area including testing pads is 1.98∗1.62 mm 2.