High gain and low noise wideband folded-switching mixer employing transformer and complimentary CS/CG hybrid topology

Abstract

In this paper, a high gain and low noise wideband folded-switching down conversion mixer has been designed. A differential complimentary common source/common gate (CS/CG) hybrid topology is utilized as the input RF transconductor stage, where a transformer is subtly applied to the source nodes of the complimentary CS/CG transistors. With the transformer and complimentary CS/CG hybrid topology as the input RF transconductor for both RF signal amplification and chip area reduction, the conversion gain, noise figure, input impedance matching, and chip area-efficiency of the mixer can be signficantly improved. Under a 0.8 ​V supply voltage and 1 ​dBm LO power, the mixer exhibits a conversion gain of 12.2–17.9 ​dB and a double-sideband noise figure of 2.6–6.1 ​dB between RF frequencies from 3.0 to 7.0 ​GHz. The IIP3 is −6.5 ​dBm at the RF frequency of 5.0 ​GHz while consuming only 2.72 ​mW of power at an IF frequency of 100 ​MHz. The chip area is only 0.55 ​mm ​× ​0.65 ​mm.