Using this circuit, you can control the speed of the 12V DC fan used in your car.The circuit is built around timer 555, which is connected as an unstable multivibrator.The output of the multivibrator is fed to THE IRF 540 MOSFET.The fan is connected between the positive electrode of the battery and the drain (D) of MOSFET T1.Capacitor C1 is connected in parallel with the fan to stabilize its speed.Continuation diode D1 protects the motor from the effects of the counter EMF.A fuse is attached for protection.
