A 189GHz Three-Stage Super-Gain-Boosted Amplifier with Power Gain of 10.7dB/Stage at Near-fmax Frequencies in 65nm CMOS

In this paper, a 189GHz three-stage super-gain boosted amplifier with power gain of 10.7dB/stage in 65nm CMOS is presented. Based on the U-boosted core and Y/Z-embedding network, a super-gain-boosting technique is proposed to improve the power gain of amplifier at near-fmax frequency. The cross-conductance technique is analyzed and exhibits the potential to improve the mason’s U of an active two port network leading to the further improvement of the theoretical upper limit of the maximum available gain (Gma). Furthermore, by employing the sensitized inductor, the sensitivity to improve mason’s U due to the process variations and modeling errors can be decreased. On top of the U-boosted core, additional Y/Z-embedding networks are employed to make Gma reach the boosted Gma_upper_limit. Based on the proposed super-gain-boosting technique, a three-stage amplifier is implemented in 65nm CMOS process, exhibits a peak small-signal gain of 32.1dB and a saturated power of -1.96dBm at 189GHz.