A low power wideband 2.6 GHz CMOS injection-locked ring oscillator prescaler

A high speed and low power prescaler based on injection-locked ring oscillator is presented. The proposed prescaler uses an adaptive biasing to increase the locking range and to eliminate the sensitivity of the locking phenomena to temperature and process variation. The designed circuit can be used in a fractional-N frequency synthesizer. Prescaler operates properly in temperature range of -20/spl deg/C to +100/spl deg/C and input frequency range from 2.2 GHz to 2.6 GHz in all process corners while its maximum power dissipation is 2 mW at supply voltage of 1.5 V.