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:
Aug. 18, 1995
W David Pricer, Charlotte, VT (US);
International Business Machine Corporation, Armonk, NY (US);
Abstract
This is an integrated timing circuit which can be formed on a microprocessor chip. The circuit uses an oscillator having a delay line and a variable delay element. The delay line and the delay element vary together to hold the velocity of signal propagation in the circuit substantially constant. The output, of the oscillator is coupled to one input of a comparator circuit. A series of inverter circuits, each of which has a respective variable delay are connected to the input of the oscillator and to a second input of the comparator circuit such that the comparator circuit senses the difference between the output signal of the inverter series and the output signal of the oscillator circuit to provide an error signal proportional to the sensed difference. A feedback loop is provided, to the variable delay means in said oscillator and to the inverter circuits to correct for the sensed difference, to establish a uniform and stable time standard at the output of the oscillator.