A 0.35-um CMOS switched-inductor dual-band LC-tank frequency divider

This paper presents a switched-inductor dual-band injection locked frequency divider (ILFD) fabricated in a 0.35-um CMOS process. The circuit is made of a differential double cross-coupled CMOS LC oscillator with a switched-inductor LC-tank, which consists of a parallel LC tank in parallel with one switched inductor composite. The dual-band function is obtained by switching the MOS switch in the inductor composite. At the supply voltage of 2.4 V, the measured free-running frequencies of the divide-by-two dual band ILFD are from 2.52 GHz to 2.61 GHz for the low-frequency band and from 4.18 GHz to 4.39 GHz for the high-frequency band. At the incident power of 0 dBm, the locking ranges of low-frequency and high-frequency band are respectively from 4.0 GHz to 5.8 GHz and from 7.1 GHz to 9.3 GHz.