A 247 and 272 GHz Two-Stage Regenerative Amplifiers in 65 nm CMOS with 18 and 15 dB Gain Based on Double-Gmax Gain Boosting Technique

Abstract

This work proposes the concept of double-Gmax (Gmax : maximum achievable gain) core based regenerative amplifier which, in principle, breaks the gain barrier of Gmax (the highest gain that can be obtained from a single transistor) at the frequencies below the maximum oscillation frequency of the transistor. Regenerative amplifiers adopting the proposed double-Gmax core are implemented in a 65 nm CMOS technology and measurements show the peak gain of 18 and 15 dB, 9 and 7.5 dB per stage, at 247 and 272 GHz, respectively.