A Variable Gain E-Band Power Amplifier using Highly Linear Embedded Attenuator

This paper presents a variable gain 81-86 GHz power amplifiers (PA) fabricated in a 0.12 μm SiGe BiCMOS technology. The PA consists of five common-emitter stages with power combining at the last stage and an intersatge linear nMOS attenuator. It achieves power gain of 24.4 dB, 14 dBm output power at 1dB compression, and saturated power of 17.1 dBm when no attenuation applied and 15 dB attenuation range. Small signal characteristics of the amplifier show peak gain at 84 GHz with 3 dB bandwidth of 12.5 GHz and 3 dB gain variation from -40°C to 85°C. The PA consumes quiescent currents of 117 mA from a 1.6 V supply and 170 mA at 1 dB compression.