Apparatus and method for monitoring fan speeds within a computing system
US6400113B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 19, 2000 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Dec 1, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/912
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
Apparatus for monitoring fan speeds within a computing system includes a tachometer turning with the fan, providing a tachometer signal including a number of pulses during each revolution of the fan. This tachometer signal is provided as an input to a signal generator in the form of a flip-flop, which generates a square-wave signal having transitions between high and low levels corresponding to tachometer signal pulses. The square-wave signals are provided as inputs to separate input ports of a microprocessor. These input ports are sequentially sampled at a rate providing at least two samples per period of the fastest square-wave signal, so that transitions of each square wave signal during a predetermined time interval can be detected and counted. For each input port, the number of counted transitions is compared to a stored acceptable value to establish whether the fan is operating in an acceptable speed range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.