A compact and low DC power distributed amplifier with cascaded gain stages using signal-reused technique in 0.18-pm CMOS

Abstract

This paper presents a signal-reused technique for distributed amplifier (DA) by using feedback transformers between the cascaded gain stages. With a proper coupling coefficient (k) of the feedback transformer, the gain-bandwidth (GBW) product of DA can be improved by extending the bandwidth of DA while maintaining the same average gain without increasing the power consumption. The DA is realized by 0.18-pm CMOS technology and it achieves an average small-signal gain of 12-dB and a small-signal bandwidth of 33.5 GHz with total dc power of 69 mW. The chip size is 0.72 mm2 including the pads.