Broadband Gilbert micromixer with an LO Marchand balun and a TIA output buffer

Abstract

A single-ended wideband downeonversion Gilbert micromixer is demonstrated in this paper using 0.35-um SiGe BiCMOS technology. Because of the wideband matching property of the micromixer, it can perform broad frequency translation. The TIA is utilized in the IF stage while a broadband Marchand balun is employed not only to generate differential LO signals but also to reserve the wideband operation of the mixer. This singleended wideband mixer has the conversion gain of 15 dB, IP(1dB) of 17 dBm, and IIP(3) of -6.5 dBm and works from 3.5 to 14.5 GHz. The input return loss is below -14 dB and the chip size is 1x1 mm(2).