Lathrop Gage LLP
Clock generator and method for reducing electromagnetic interference from digital systems
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.
OmniVision Technologies, Inc.
H H H H H H H H H H H
H03K H04L H03K H04B H03K H03K H03K H03L H04L H04B H03K
inventional inventional inventional inventional additional inventional inventional inventional inventional inventional inventional
Charles Qingle Li Wengen
Wu Yang Wang