An ultra low power frequency divider for 2.4GHz ZigBee frequency synthesizer

This paper introduces an ultra low power frequency divider utilized in Integer-N frequency synthesizers, which operates in 2.4GHz IEEE 802.15.4/ZigBee frequency band. The proposed frequency divider consists of a dual modulus prescaler and a divide-by-64. In order to reduce the power consumption, Swallow counter has been replaced by a simple digital circuit. Simulation results exhibit 410μw power consumption for 4 bit frequency divider in 2.4GHz frequency band that proves 40% reduction compared to previous works. All of the circuits have been designed in 0.18μm TSMC CMOS technology with a single 1.8V dc voltage supply.