Analysis and Design of Digital Injection-Locked Clock Multipliers Using Bang-Bang Phase Detectors

Abstract

The analysis of injection-locked clock multipliers (ILCMs) using bang-bang phase detectors (BBPDs) is challenging due to the nonlinear BBPD and the multi-rate injected oscillator. This paper presents an explicit analysis of digital ILCMs using BBPDs and proposed an intuitive approach to optimizing parameters with given noise sources. A time-domain analysis in the single-clock domain is presented to solve the closed-form expression of jitter in the ILCM. The proposed approach exhibits good consistency with simulations, for various design parameters and noise cases. With the predicted input-referred jitter, the equivalent BBPD gain is resolved to derive the frequency-domain noise transfer functions in concise forms. To achieve the desired performance with given specifications, recommended design procedures are summarized based on the proposed analysis and verified by simulations.