| 摘要 |
A fan driver circuit is provided to prevent unnecessary operation and noise of a fan by automatically turning on/off the fan in accordance with the temperature. A fan driver circuit comprises a transistor(Q2) which is turned on by receiving driving voltage through a base; a resistor(R1) for receiving power of a vehicle or an electronic product; a resistor(R2) having one end serially connected to the resistor(R1) and the other end which is grounded so as to cooperate with the resistor(R1) to distribute power of the vehicle or the electronic product; a transistor(Q1) which is turned on by receiving power of the vehicle or the electronic product through an emitter and receiving voltage of the resistor(R2) through a base when the first transistor is turned on; a resistor(R3) having one end connected to a collector of the transistor(Q1); a resistor(R4) having one end connected to the other end of the resistor(R3) and the other end which is grounded; a temperature sensor which has a resistance component, and is connected to the resistor(R4) in parallel; a transistor(Q3) which is turned on by receiving voltage distributed by resistors(R3,R4) and the resistance component of the temperature sensor, and passes power of the vehicle or the electronic product provided through the collector of the transistor(Q1); a resistor(R5) for dropping voltage of power of the vehicle or the electronic product provided through a collector of the transistor(Q3); and a transistor(Q4) which is turned on by receiving voltage dropped by the resistor(R5) through a base, and provides power of the vehicle or the electronic product to a fan. |
