A 16.4-dBm 20.3% PAE 22-dB Gain 77 GHz Power Amplifier in 65-nm CMOS Technology

We present a compact W-band power amplifier (PA) for automotive radar application in 65-nm CMOS technology. The circuit adopts a pseudo-differential push-pull configuration based on transformers (TFs) which offer highly efficient and flexible matching networks with minimized area occupancy. We have set the optimal output resistance close to 50 Omega, design guidelines in sizing active devices for each stage, and the corresponding transformers were presented for optimal power efficiency based on an analysis of surrounding matching networks. Working under a supply voltage of 1.3-V, the implemented 77GHz PA achieved a 3-dB gain bandwidth of 9-GHz (72.5-81.5 GHz), a peak gain of 22.4 dB, a saturated power (P-s(at)) of 16.4 dBm, and a peak power-added efficiency (PAE) of 20.3%. The area for the core layout is only 0.05 mm(2), which demonstrates the highest power density among the recently reported W-band CMOS PAs.