Sub-mW multi-GHz CMOS dual-modulus prescalers based on programmable injection-locked frequency dividers

Dual-modulus prescalers based on programmable injection-locked frequency dividers (ILFDs) are presented. With a multi-phase injection, variable division ratios are obtained by simply switching different number of input signals. Implemented in a 0.18 mum CMOS process, the 4/5 dual-modulus prescaler achieves an operating range of 1.8-6 GHz with 0.22 mW measured power consumption from a 1 V supply. Based on the same architecture, a 0.15 mW 5 GHz 2/3 dual-modulus prescaler and a 0.29 mW 5.5 GHz 8/9 dual-modulus prescaler are also demonstrated.