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:
Sep. 30, 1997
Filed:
Apr. 15, 1996
Nandor Gyorgy Thoma, Plano, TX (US);
Trong Duc Nguyen, Austin, TX (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A signal delay device is provided which enhances noise immunity by using a differential circuit, but also maintains the phase of the input clock signals. This device will also correct the phase of clock signals which are input to the delay device in an out of phase condition. The present invention is a delay circuit that includes functionally connecting each of the output signals with each of the input signals. Thus, the output signals are dependent on the same input and the steady state condition is the point where the leading edge of a first output signal intersects the trailing edge of a second output signal at the point which corresponds to one half of the pulse height of both signals. Since the signals are complements of one another, they will cross at 50% of their pulse height when they are 'in phase'. Thus, the present invention will maintain 'in phase' input signals and seek an 'in phase' condition for signals that are input to the delay circuit which are 'out of phase'.