LC-tank divide-by-4 injection-locked frequency divider using the second-order harmonic feedback.

A low voltage, wide locking range and operation range divide-by-4 injection-locked frequency divider (ILFD) is proposed in the paper and the ILFD was fabricated in the TSMC 90 nm RF-CMOS process. The divide-by-4 ILFD uses a cross-coupled voltage-controlled oscillator (VCO) with a parallel-tuned LC resonator and a three-transistor composite that acts as a linear and nonlinear mixer. At a drain-source bias of 0.6 V and at an incident power of 0 dBm, the operation range of the divide-by-4 ILFD is 5.3 GHz, from the incident frequency 21.1 GHz to 26.4 GHz, and the percentage of operation range is 22.31%. The locking range of the divide-by-4 ILFD is 1.4 GHz, from the incident frequency 21.1 GHz to 22.5 GHz, and the percentage of locking range is 6.42%. The core power consumption is 2.58 mW. The die area is 0.86 × 0.75 mm2. [ABSTRACT FROM AUTHOR]