A 110GHz inductor-less CMOS frequency divider

An inductor-less 110 GHz ring-type frequency divider (RILFD) has been proposed. Body-injection and biasing technique have been adopted to achieve high speed and divide-by-three operation and fine tuning of operation frequency. The RILFD was fabricated by a 1P12M 65 nm bulk CMOS process. The core size is 10.8×8.5 ¿m2. The locking range is 9.1%, from 100.8 to 110.4 GHz, under varying of body-bias voltage from -0.2 V to 0.4 V. The RILFD consumes 4.5 mW at the supply voltage of 1 V excluding an output buffer. The output phase noise is -117.6 dBc/Hz at 1 MHz offset. This work has been achieved the smallest core size among frequency dividers reported to date operating over 100 GHz.