A 23.5-dBm, 7.9%-PAE Pseudo-differential Power Amplifier at 136 GHz in 40-nm GaN
Eythan Lam, Andrea Arias-Purdue, Everett O’Malley, James F. Buckwalter
Abstract
A pseudo-differential power amplifier (PA) is demonstrated at 136-GHz in a 40-nm GaN HEMT technology. The 2-stage design achieves an output power of 23.5 dBm and peak power-added efficiency (PAE) of 7.9% with an associated gain of 7.6 dB. To improve the overall gain in this frequency band, the design incorporates HEMT cells with 3-via inductive source degeneration for gain peaking and improved compression. Pseudo-differential power combining is also implemented using on-chip Marchand baluns with common-source devices. The PA area is 1.26 x 1.13 <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$mm^{2}$</tex> . To the author's knowledge, this compact PA demonstrates the highest power added efficiency (PAE) in GaN above 135 GHz.