A 24-GHz transformer-based single-in differential-out CMOS low-noise amplifier

This paper presents a 24-GHz single-in differential-out (SIDO) CMOS low-noise amplifier (LNA) for wireless communication applications. The SIDO LNA utilizes a trifilar transformer inserted between the first and the second stages for the single-to-differential signal conversion. The LNA, fabricated in a 0.13 mum RF CMOS technology, exhibits a differential gain of 14.7 dB, a 3-dB bandwidth of 3.5 GHz (from 22.9 to 26.4 GHz), a noise figure of 4.3 dB, and an input 1-dB compression point (P_1dB) of -13 dBm at 24 GHz. The gain and phase difference are 0.6 dB and 0.47deg, respectively, which demonstrates well balanced characteristics.