A dual-level and dual-band class-D CMOS power amplifier for iot applications

In this paper, a dual-level and dual-band Class-D CMOS power amplifier (PA) in a standard 0.18μm CMOS process is presented for Internet of Things (IoT) applications. With a tunable power amplifier stages controlled by a single bit switch, the proposed PA enables the dual-level operation, low and high output power modes. At the high level mode, all the stages are turned on, and at the low level output power mode, the stages are scaled while only part amplifiers work in order to maintain the PAE performance over a wide range of output power levels. Exploiting a tunable band matching network, the PA can also provide dual-band operation. Experimental results indicate that the proposed amplifier provides greater than 20dB gain, 16-19dBm output power at the 600/780MHz bands. The measured maximum efficiencies of the dual-band PA are 36.6% and 46.66% for the low output power mode and high output power mode, respectively.