Back to results
US 7,841,837 B2Granted
Cooling-fan rotation-speed control circuit
AssigneeZippy Technology Corp.
InventorTsung-Chun Chen
Life of this patent
Estimating the term…
Abstract
The present invention discloses a cooling-fan rotation-speed control circuit, wherein a plurality of sets of input power sources respectively having different voltages is electrically and parallel coupled to a cooling fan; a switch is installed between at least one input power source and the cooling fan; the switch is turned on/off according to a rotation-speed parameter to determine whether the cooling fan is driven by a low-voltage driving power or a high-voltage driving power.
Claims7
A cooling-fan control circuit, used to determine the rotation speed of at least one cooling fan, said control circuit comprising:
- at least two separate input power sources that provide power to drive said cooling fan, said input power sources including a low-voltage input power source and at least one high-voltage input power source which supply electric current to said cooling fan through separate power-providing lines, said low-voltage input power source being electrically coupled to said cooling fan continuously;
- a separation element installed between said low-voltage input power source and said cooling fan;
- and
- a switch installed on at least one power-providing line between at least one said high-voltage input power source and said cooling fan, acquiring a rotation-speed parameter to determine the on/off setting of said switch and thereby determine whether said cooling fan is driven by the low-voltage input power source or one of the high-voltage input power sources according to said rotation-speed parameter.
1 more element
Dependencies are inferred from the claim text.