High-gain mixer using cascode current bleeding and g(m)-boosting techniques

Abstract

This paper presents a high-gain down-conversion mixer using a cascode current bleeding technique and a transconductance (g(m))-boosting technique. Unlike the conventional folded-type mixer, an nMOS input transconductance transistor is allocated under pMOS switching transistors and load resistors in the proposed mixer. This topology allows the folded mixer to reuse the total current at the input transconductance transistor for low power consumption and to adopt the current bleeding technique for high gain. In addition, the g(m)-boosting technique increases effective transconductance by adding a positive-feedback inductor. Measured results show a maximum voltage conversion gain of 23.8 dB, an input third-order intercept point (IIP3) of -10.5 dBm at the maximum gain, a minimum noise figure of 4.3 dB, and a 3-dB bandwidth from 7.2 to 8.4 GHz with a consumption of 3.9 mW from a 1.2 V supply. The chip size, including test pads, is 0.9 x 0.95 mm(2) using 0.13 m RF CMOS technology.