A 0.13µm CMOS ΔΣ fractional-N synthesizer for WiMAX application

This paper presents a fully integrated WiMAX frequency synthesizer. This synthesizer operation frequency is from 4.4 GHz to 5.5 GHz. It is a DeltaSigma fractional-N synthesizer. It consist of an on-chip low drop out (LDO) regulated LC-VCO, a sigma delta noise shaper, a divider, and a high linearity charge pump. This synthesizer has been implemented in 0.13 mum CMOS technology and occupied 1.2 mm
²
area. It draws 32 mA and consumes 38.4 mW from a 1.2 V supply. The measured out-band phase noise at 1 MHz offset is -117 dBc/Hz. The integrated phase noise is less than 1.25deg.