A Wide-Locking-Range Dual Injection-Locked Frequency Divider With an Automatic Frequency Calibration Loop in 65-nm CMOS

摘要

This brief presents a wide-locking-range injection-locked frequency divider (ILFD) that uses an automatic frequency calibration loop. The proposed ILFD uses the ring oscillator to provide the high division ratio with small chip area. A dual-injection scheme is proposed in order to achieve the wide locking range of the ILFD. The free-running frequency of the ILFD is automatically digitally calibrated to reflect the frequency of the injected signal from the voltage-controlled oscillator. To control the frequency of the ILFD, the load current is digitally tuned with 3-bit control signal. The ILFD is fabricated using 65-nm CMOS process, and by tuning the load current, it achieves the wide operation frequency range of 14.1–45.8 GHz. When the input signal of 30 GHz is injected, the locking range of the ILFD is 7.2 GHz, while the power consumption is 2.5 mW from a 1-V supply voltage.