An E-band Variable-Gain Amplifier Using a Programmable Attenuator

In this paper we present a programmable variable-gain amplifier (VGA) for a 5G demonstration system at E-band. The proposed VGA consists of a common-base amplifier and a variable loss attenuator controlled by a novel programmable feedback circuit. The attenuator is based on a differential π network and it covers 12 dB of range with a 0.5 dB step size. The circuit is implemented in a 55 nm BiCMOS technology and it achieves maximum gain of 4.8 dB and worst case RMS phase error of 2.6° over 71 GHz - 76 GHz. The total power consumption of our design is 18.4 mW from a 1.6 V supply voltage.