Superharmonic injection-locked frequency dividers

Injection-locked oscillators (ILOs) are investigated in a new theoretical approach. A first-order differential equation is derived for the noise dynamics of ILOs. A single-ended injection-locked frequency divider (SILFD) is designed in a 0.5-/spl mu/m CMOS technology operating at 1.8 GHz with more than 190 MHz locking range while consuming 3 mW of power. A differential injection-locked frequency divider (DILFD) is designed in a 0.5-/spl mu/m CMOS technology operating at 3 GHz and consuming 0.45 mW, with a 190 MHz locking range. A locking range of 370 MHz is achieved for the DILFD when the power consumption is increased to 1.2 mW.