A V-band Double-Transformer-Coupling and Current Steering VGLNA in 90-nm CMOS

This paper presents a broadband (50-67GHz) variable gain low noise amplifier (VGLNA) with low dc power in 90-nm CMOS technology. A double-transformer-coupling (DTC) technique is used to improve gain and noise performance of the LNA. The variable gain function is implemented using a combination of DTC and current steering (DTCCS) techniques. With DTCCS technique, not only the power consumption can be reduced, but also the variable gain function can be implemented. The measured peak gain is 17.1 dB with a 3-dB bandwidth that covers from 50 to 67 GHz, and an 8-dB gain control range. The measured minimum noise figure (NF) is 5.8 dB. The measured IP1dB at the high gain state is -25 dBm. The VGLNA consumes only 5.7-mW dc power with a compact chip area of 0.6 x 1 mm(2).