A 60GHz-band 20dBm power amplifier with 20% peak PAE

A three-stage, 60GHz transformer-coupled differential power amplifier is implemented in 130nm SiGe-BiCMOS. Common-base differential pair stages extend BVCEO, while neutralization increases isolation, promoting stability. Self-shielded transformers, a parasitic-compensated 4:1 output combiner and 2:4 input splitter are designed for low insertion loss and compact dimensions on-chip. Measured small-signal gain is >;20dB with over 10GHz -3dB bandwidth. Reverse isolation is better than 51dB across 50-65GHz. Maximum output power and peak-PAE are 20.5dBm and 20%, respectively, at 61.5GHz. The PA consumes 353mW from a 1.8V supply and 0.25mm² active area.