Fan control circuit

The utility model discloses a fan control circuit, including electrode slice A, electric capacity C1, chip IC1 and bidirectional thyristor Q1, its characterized in that, electrode slice A connects electric capacity C1, and electric capacity C1's other end connecting resistance R1, resistance R1's other end connecting resistance R3 and transient voltage restrain diode D3, resistance R3's other end connection chip IC1's pin 4, chip IC1's pin 1 connecting resistance R2. The utility model discloses fan control circuit circuit structure is simple, components and parts are few, adopts the step -by -step touch of the fourth speed to adjust luminance application specific integrated circuit PT2102 as keeping off a position regulatory element, the rotational speed of control fan that can be convenient, simultaneously circuit arrangement power failure auto -lock module, run into the back self -closing that has a power failure, prevent that the electric energy that incoming telegram back self -starting brought is extravagant, consequently have and practice thrift the advantage that electric energy, convenient to use and cost of manufacture are low.