Wide-locking range LC-tank divide-by-4 injection-locked frequency divider using transformer feedback.

ABSTRACT A wide locking range, injection locked frequency divider (ILFD) circuit topology is explored. The modulus-four ILFD utilizes a cross-coupled voltage-controlled oscillator in conjunction with transformer feedback, parallel-tuned resonator, and two-segment, series mixers at the injection point. The transformer feedback and two-segment mixing circuit topology achieves a locking range of 2.7 GHz (14.1 to 16.8 GHz) at an injection point bias of 0.9 Vdc and 0 dBm injection power. Spectral measurements at the ILFD output demonstrate proper phase-lock operation and expected phase noise reduction using a high quality signal source at the ILFD input. The ILFD is implemented in the TSMC 0.18 μm 1P6M CMOS process, utilizes a die area of 0.839 × 0.566 mm2 and consumes 16.56 mW. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:557-562, 2015. [ABSTRACT FROM AUTHOR]