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:
Jun. 29, 2004
Filed:
Jan. 23, 2001
Robert Christopher Dixon, Austin, TX (US);
Chad J. Larson, Ames, IA (US);
International Business Machines Corporation, Armonk, NY (US);
Abstract
A multiple fan monitoring circuit for use with a plurality of fans, wherein each of the fans operates at a different frequency and generates a tach signal indicative of the fan operation, including a number of waveform shaping networks coupled to a corresponding one of the fans and utilized to waveshape a tach signal generated by its corresponding fan. The multiple fan monitoring circuit also includes a frequency processing circuit, coupled to the waveform shaping networks, that receives the waveshaped tach signals at a single sense node. The frequency processing circuit includes a summing circuit, coupled to the single sense node, that combines the waveshaped tach signals into a single combined signal, and a frequency discriminator, coupled to the summing circuit, that separates the single combined signal into multiple components, wherein each of the multiple components corresponds to a particular fan.