Wide‐locking range single‐injection divide‐by‐3 injection‐locked frequency divider

Abstract

This letter presents a wide-locking range CMOS divideby-3 injection-locked frequency dividers (ILFD) using single-ended injection signal. The fabricated 0.18 lm CMOS 43 ILFD uses crosscoupled switching transistors, single-injection MOSFET, and a dualresonance RLC resonator. The consumed power of the 43 ILFD core is 7.97 mW at the DC drain-source voltage 0.76 V. At an external injected signal power P inj 5 0 dBm, the measured locking range is 2.97 GHz (25.25%) from 10.28 to 13.25 GHz and the operation range is 5.17 GHz (48.5%) from 8.08 to 13.25 GHz.

Wide‐locking range ÷3 injection‐locked frequency divider using direct‐injection and switching‐injection techniques

“…The latter is attractive because it can selfgenerate a push-push signal, by which linear mixer is used to design the wide-band ILFD instead of the past harmonic mixer approach. Two other important techniques for extending locking range are based on capacitive-cross-coupled oscillator [6,7] and multi-resonance resonator [8,9]. The present ILFD unifies the above-mentioned techniques to get wide-band locking range.…”

Review of Injected Oscillators

“…Due to the small locking range of injected LC oscillators, various techniques have been realized to enhance the locking range. Passive and active structures are explored for improving the injection efficiency such as combining inductors in series or parallel with the injection mixer to enhancing its transconductance, body biasing, transformer feedback, dual-resonance RLC resonators, dual injection for increasing the voltage and current injection paths, tapped resonators, switched resonators, harmonic suppression, and distributed injection to distribute the injection signals; in other words, the injection component is divided to several smaller components; input-power-matching and inductive input-matching network is located to the gate of the NMOS switch to heighten the injection power [63][64][65][66][67][68][69][70][71][72]. Figure 6 discloses a quadrature LC oscillator employed in the injection signal.…”