A Wideband Bi-Directional Gain Amplifier with Asymmetric Cell using Cascade Gain Boosting in 65nm CMOS Process

Abstract

A bidirectional distributed gain amplifier (BDGA) with asymmetric cell combined with a cascade gain boosting structure is presented in this paper. Conventional DA designs generally have the gain limitation because of the additive gain mechanism, whereas the proposed structure can benefit significantly from the multiplicative gain mechanism due to the cascade of two BDGAs. Moreover, the unit gain cells are intentionally designed to be asymmetrical with the common source (CS) configuration at output stages to improve the output power of the circuit. The proposed circuit architecture is fabricated in a standard 65 nm CMOS. The measurement results show the gain of 10.5 dB, and the 3-dB bandwidth from 5.8 - 17.6 GHz. The measured output P1dB is 6.8 dBm along with 9.3 dBm of the saturated output power at 10 GHz. The circuit draws a current of 75 mA from a 1.2 V supply and occupies 1.1 x 0.6 mm2 of chip area.