A V-Band CMOS Divide-by-Three ILFD With Frequency-Dependent Injection Enhancement

This letter presents a V-band divide-by-three injection-locked frequency divider (ILFD) with low power consumption and wide locking range, by using the novel frequency-dependent injection enhancement (FDIE) technique. The optimum tradeoff between amplitude and phase locking conditions of the FDIE circuit is first analyzed theoretically. Then a current-reused differential pre-amplifier loaded with a moderate-k transformer for FDIE circuit is proposed to obtain the greatest locking range under such trade-off. Fabricated in a 65 nm CMOS technology, the proposed ILFD prototype demonstrates a wide input locking range of 54.5-62.36 GHz (13.5%) and only 2.5 mA current consumption with 1.2 V supply.