Wideband Phase-Compensated VGA with PMOS Switch in 40-nm CMOS for 120-GHz Band

This paper presents a 120-GHz wideband phase-compensated variable gain amplifier (VGA) with a p-type metal–oxide–semiconductor (PMOS) switch using a 40-nm CMOS process. By applying a PMOS switch to the common source (CS) amplifier, the gain of the CS amplifier can be controlled by as much as 6.1 dB with 2° phase variations in 15.1-GHz bandwidth ranging from 100.9 to 115 GHz. The measured gain and 3-dB bandwidth of the VGA are 19.1 dB and 33.8 GHz for high-gain state, and 13 dB and 44.2 GHz for low gain state, respectively. Meanwhile, the DC power consumption in the high-gain state is 45 mW, and the OP1dB is −2.7 dBm.