Design of a Wideband High-Voltage High-Efficiency BiCMOS Envelope Amplifier for Micro-Base-Station RF Power Amplifiers

A high-performance bipolar-CMOS-DMOS (BCD) monolithic envelope amplifier for micro-base-station power amplifiers (PAs) is presented. Measurement of the BCD high-voltage (VDD = 15 V) envelope amplifier shows an efficiency of 72% using 7.7-dB peak-to-average ratio WCDMA input signals at an average envelope amplifier output power above 3 W. A WCDMA envelope-tracking RF PA at 2.14 GHz, including a GaN field-effect transistor RF stage, has an overall drain efficiency above 51%, with a normalized power root-mean-square error below 1.2% and an adjacent channel leakage ratio of -49 dBc at 5-MHz offset using memory-effect mitigation digital pre-distortion, at an average output power above 2 W and a gain of 10 dB.