A 90‐NM CMOS low‐power down‐converter for 3‐ to 5‐GHz ultra‐wideband wireless systems

This article presents the design and the measurement results of a 3‐to 5‐GHz down‐converter fabricated in a 90‐nm CMOS technology. The circuit consists of a single‐ended low‐noise amplifier and two I/Q double‐balanced mixers. A transformer‐based on‐chip single‐ended‐to‐differential conversion allows gain and noise performance to be optimized at a very low power. The down‐converter achieves a 23‐dB conversion gain, a noise figure of 3.4 dB, and an input third‐order intercept point of −8 dBm, while drawing only 9 mA from a 1.2‐V supply voltage. The down‐converter exhibits competitive performance compared to the best state‐of‐the‐art ultra‐wideband circuits in the same frequency range. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2577–2581, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23744