A 220-GHz High Linearity Power Amplifier with 25.7-dB Gain and 9.7-dB PSAT

In this brief, a 220-GHz power amplifier (PA) utilizing a three-stage differential cascode (CC) configuration is presented. The PA employs the gm-boosting technique and a ladder-type interconnection method to enhance gain and output power in 0.13-µm SiGe BiCMOS process. To achieve better performance, it utilizes modified Marchand baluns (MBLs) with metal-oxide-metal (MOM) capacitors instead of transformer-based baluns (TBLs) for signal transformation from single-ended to differential (S2D). Simulated results demonstrate that this PA presents a peak gain of 25.8 dB at 217 GHz, PAE of 1.9%, and P
SAT
/OP
1dB
up to 9.7/7.7 dBm within the bandwidth. Compared to other silicon-based differential PAs operating above 210 GHz, this circuit shows excellent linearity, with 1-dB compression point 2 dB less than saturation.