公开(公告)号：US09900145B2

公开(公告)日：2018-02-20

申请号：US15159583

申请日：2016-05-19

Applicant: OmniVision Technologies, Inc.

Inventor： Li Yang ,  Wengen Wang ,  Charles Qingle Wu

IPC: H03D3/24 ,  H04L7/033 ,  H04L5/00 ,  H04B1/69

CPC classification number: H04L7/0331 ,  G06F1/08 ,  H03K3/84 ,  H03K5/00 ,  H03K5/1252 ,  H03K5/131 ,  H03K5/133 ,  H03K5/14 ,  H03L7/16 ,  H04B1/69 ,  H04B15/02 ,  H04L5/005

Abstract: A spread-spectrum clock generator has a phase-locked loop locked to a reference signal that gives a stable-frequency output to a variable phase shifter. The variable phase shifter provides a spread-spectrum clock output because its phase-shift is determined by a pseudorandom sequence generator and the pseudorandom sequence generator changes its output regularly or irregularly within limits. The clock generator performs a method of generating a spread-spectrum clock including locking the phase-locked loop to the reference signal, and phase shifting the stable frequency signal by a phase-shift determined by the pseudorandom sequence generator; and changing the phase-shift determined by the pseudorandom sequence generator. Since phase shifting is performed open-loop, total phase shift is defined by design.