A W-Band Divide-by-Three Injection-Locked Frequency Divider with Injection Current Boosting Utilizing Inductive Feedback in 65-nm CMOS

A compact W-band divide-by-three injection-locked frequency divider (ILFD) is presented in 65-nm CMOS technology. To provide a wide locking range, we propose inductive feedback to boost the injection current. With the proposed approach, the locking range of the ILFD can be wider than 10% without any varactor and additional power dissipation which is more than three times the locking range compared with the reference ILFD without boosting of the current injection. The measured locking range of the proposed ILFD was from 73.9 to 82.5 GHz with the W-band input signal power of 0 dBm, and the phase noise at 1 MHz was -117.13 dBc/Hz at the input frequency of 78 GHz. The implemented ILFD with the inductive feedback consumes 7.88 mW under a 1 V supply, and its core size is 0.22