A wide range quadrature injection-locked frequency divider

Abstract

This article presents a wide-locking range divide-by-2 quadrature injection-locked frequency divider (QILFD) with capacitive cross-coupled oscillator. The ILFD consists of a quadrature voltage controlled oscillator (QVCO) and two NMOS switches, which are in parallel with the QVCO resonators for signal injection. The proposed CMOS QILFD has been implemented with the TSMC 0.18-μm CMOS technology and the core power consumption is 7.434mW at the supply voltage of 0.9V. The free-running frequency of the QILFD is tunable from 2.38 GHz to 2.48GHz. At the input power of 0dBm, the divide-by-2 locking range is 116.521% from 2.4 GHz to 9.1 GHz. The phase noise of the locked output spectrum is lower than that of free running QILFD in the ÷ 2 mode.