Apparatus and method for fan auto-detection
US7791301B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 2, 2008 |
| Grant date | Sep 7, 2010 |
| Priority date | — |
| Expiry date | Oct 17, 2028 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/934
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An apparatus for detecting a type of fan and controlling the fan, the fan providing during operation a tachometer signal indicating a speed of the fan, the apparatus includes: a direct current (DC) generator for coupling to the fan and configured to provide a first voltage to the fan; a resistor for providing, while the DC generator provides the first voltage, a sensed voltage relating to the type of the fan, wherein the resistor is connected to a reference voltage and for coupling to a pulse-width modulation (PWM) control terminal of the fan; an input judgment component coupled to the resistor to receive the sensed voltage, the input judgment component being configured to determine whether the fan is a 4-wire PWM fan with an internal pull-up resistor based on the sensed voltage and to provide a judgment signal indicating the determination; a PWM generator coupled to the input judgment component to receive the judgment signal, the PWM generator being configured to provide to the fan a PWM control signal to control the fan if the judgment signal indicates that the fan is the 4-wire PWM fan with an internal pull-up resistor; and a tachometer coupled to the DC generator and the PWM ge…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.