Abstract
A dual-modulus prescaler based on a multi-phase quasi-differential locking divider is presented. It direclty modulates the output in a multi-phase ring oscillator by quasi-differential injection. Dual-modulus operation is achieved by change of the number of injected signals. It is suitable for low supply operation while a wide locking range is obtained. Implemented in a standard 0.18 mu m CMOS process, the 4/5 dual-modulus prescaler achieves an operating range of 1.1-5.6 GHz with 0.8 mW measured power consumption from a 1.2 V supply.