Low voltage 2-mW 6/spl sim/10.6-GHz ultra-wideband CMOS mixer with active balun

• Published in: 2006 IEEE International Symposium on Circuits and Systems (ISCAS) p. 4 pp.
• Main Authors: Ta-Tao Hsu, Chien-Nan Kuo
• Format: Conference Proceeding
• Language: English
• Published: IEEE 2006
• Subjects: Circuits; CMOS technology; Impedance matching; Low voltage; MOS devices; Operational amplifiers; Radio frequency; Radiofrequency amplifiers; RF signals; Ultra wideband technology
• ISBN: 0780393899; 9780780393899
• ISSN: 0271-4302; 2158-1525
• DOI: 10.1109/ISCAS.2006.1693930

A low-voltage and low-power CMOS mixer with an active balun is designed for frequency down-conversion in ultra-wideband applications. The mixer contains CMOS amplifiers as the LO buffer and the modulating stage in a folded configuration to allow low-voltage operation. The RF input signal comes from a new low-power active balun that uses a pair of common-source NMOS and common-gate PMOS transistors. This balun gives an impedance transformation ratio of 1:2, and provides a differential signal within 0.5dB and 1.5deg of gain and phase imbalance, respectively, from 6 to 10.6-GHz. The mixer and the active balun are designed in 0.18mum CMOS technology to operate at 1.2-V supply voltage. The circuit performance of the mixer with the active balun achieves flat conversion gain of 17 dB within 1 dB variation, the maximum IIP3 of 0 dBm, and the minimum noise figure of 13 dB. The total circuit only consumes power of 2 mW. As compared to typical designs, it saves about 85% and 95% of power consumption in the balun and the mixer circuits, respectively