79GHz BiCMOS Single-Ended and Differential Power Amplifiers

This paper presents the performance of 79GHz power amplifiers (PAs) for automotive short range radar (SRR) application. A single-ended four stage common emitter circuit topology and a differential PA with integrated baluns are fabricated using 0.13) m SiGe BiCMOS process. The design and the measured results of the monolithic integrated low-voltage PAs are reported. The 79GHz differential PA, which the design is based on the single-ended PA, delivers 18dBm of maximum output power and 13.5dBm output power at 1dB compression (P-1dB). The differential circuit achieves 21.5dB gain and shows 8.2% of power added efficiency (PAE) from a 1.8V supply voltage at 79 GHz. The power amplifier was fully integrated including matching elements, bias circuit and very small baluns. The chip occupies an area of 0.46mm(2) and 0.7mm(2) for the single-ended and differential configuration respectively.