A Fully Integrated Adaptive Multiband Multimode Switching-Mode CMOS Power Amplifier

Abstract

This paper presents a fully integrated adaptive multiband multimode switching-mode power amplifier (SMPA) in CMOS technology. The power amplifier (PA) module, consisting of input matching, driver, output stage, load transformation network (LTN), and auxiliary circuitry, utilizes optimized driving waveforms to increase output power and efficiency of a SWPA. The PA module is packaged in a 32 quad flat no-lead package. Based on the detailed analysis on appropriate driving waveforms, the SMPA is designed to maximize its output power and efficiency with minimum on-chip harmonic terminations. Furthermore, an adaptive gain control technique is proposed to control the SMPA gain at back-off while boosting the power-added efficiency (PAE) using a fully integrated tunable LTN. Employing both techniques concurrently enables us to have a multiband multimode SMPA. Measurements on a PA module designed in 90-nm CMOS and incorporating theses findings result in peak PAE of 43% for an output power of 27.1 dBm, associated with a large-signal gain of 22.1 dB at 1.97 GHz, when the devices are biased at 2.8 V. With the tunable LTN PAE at 4- and 6-dB backoff is 30% and 23%, respectively. To our knowledge, this is the first fully integrated multiband multimode SMPA in CMOS technology.