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. 07, 2010
Filed:
Jan. 02, 2008
Shih-feng Huang, Hsinchu, TW;
Chia-ching LU, Hsinchu, TW;
Ming-che Hung, Hsinchu, TW;
Nuvoton Technology Corporation, Hsinchu, TW;
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 generator, the tachometer being configured to receive the tachometer signal to detect a change in the speed of the fan.