Design of a low-power high-speed CMOS frequency divider for WSN applications

A 5-GHz CMOS programmable frequency divider is presented in this paper, whose modulus can be varied from 2403 to 2480 for 2.4-GHz ZigBee applications. The divider has two blocks, a dual-modulus prescaler (DMP) integrating a frequency halving circuit, and a pulse-swallow counter. In the DMP, an improved phase switching technique is used to reduce the power consumption. Designed in 0.18-μm CMOS process, simulation shows that the divider can operate over a wide range of 1-6.5 GHz, consumes 7.7 mW from a single 1.8 V supply, and occupies a chip area of approximately 0.02 mm².