The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 27, 2004
Filed:
Aug. 27, 1998
Hitachi, Ltd., Tokyo, JP;
Abstract
An oscillation circuit provides clock signals and a clock distribution circuit or system of circuits having low skew and low jitter to logic circuits and memory circuits of a microprocessor or the like. Further, a semiconductor integrated circuit device of high speed is provided as a result of the stable clock signal that is generated and distributed. The oscillation circuit is in a semiconductor integrated circuit device having a plurality of oscillators each having an oscillation node, wherein the oscillation nodes of each of the oscillators are connected together by a conductive wiring line that may be a closed loop. The oscillators are synchronized to oscillate at substantially the same frequency. The oscillators are connected to the conductive wiring line at connecting points having substantially the same interval of conductive wiring lengths between the connection points, which leads to synchronizing the oscillators to oscillate with a substantially identical phase. The conductive wiring line can also be formed in the shape of a mesh with the interval of length of the conductive wiring line between the connection points being at least 50 &mgr;m. The oscillators are ring oscillation circuits having inverters connected in a ring shape wherein an output of at least one inverter of each ring oscillation circuit is connected to the conductive wiring. Alternatively, the oscillators may be delay lines having multistage connected inverters with at least one inverter connected to the conductive wiring line.