Patent ID: 8368338
Filing Date: 2013-02-05
Classification: G06F,H05K

Abstract:
1. A device for detecting a type of a fan connected with a fan having a voltage input terminal, the device comprising: a detector for detecting a control voltage of the voltage input terminal and comparing the control voltage with a reference voltage to generate a comparison signal; and a voltage controller receiving a modulation signal, a constant voltage, and the comparison signal, wherein when the control voltage is smaller than the reference voltage, the voltage controller converting the modulation signal to a variable voltage and outputting the variable voltage to the voltage input terminal of the fan, when the control voltage is greater than the reference voltage, the voltage controller outputting the constant voltage to the voltage input terminal of the fan, wherein the voltage controller further comprises: a selector for receiving the constant voltage and the modulation signal, wherein when the control voltage is smaller than the reference voltage, the selector outputting the modulation signal, when the control voltage is greater than the reference voltage, the selector outputting the constant voltage to the voltage input terminal of the fan; and an integrator connected with the selector and the fan for receiving and integrating the modulation signal into the variable voltage and outputting the variable voltage to the voltage input terminal of the fan.