A 1-V, 9.7mW CMOS frequency synthesizer for WLAN 802.11a transceivers

A 1-V CMOS frequency synthesizer is proposed by using a transformer-feedback VCO for low voltage and a stacked divider for low power. Implemented in 0.18-/spl mu/m CMOS process, the synthesizer is operated with a 1 V supply while consuming 10mW and occupying an area of 1.28mm/sup 2/. It measures a phase noise of -139dBc/Hz at an offset of 20MHz with a center frequency of 4.256GHz. The frequency tuning range of the frequency synthesizer is measured from 4.114-4.352GHz with a total number of 16 channels.