| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a fan drive circuit capable of surely starting revolutions and reducing circuit power when a fan stops. SOLUTION: This circuit contains a fan control switch 4 which is subjected to ON/OFF control by a control signal of a CPU operation confirmation circuit, a fan 7 whose voltage is applied by such a manner that the switch 4 is turned on and which is for cooling a CPU and a temperature variable speed control circuit 5 whose operation is started by such a manner that the switch 4 is turned on to apply a power supply voltage and which monitors CPU temperature and controls the speed of the fan 7. The circuit 5 is provided with a deflection circuit operating so as to give a maximum voltage to the fan 7 when the operation starts by the on of the switch 4 and monitors the CPU temperature by a thermistor 12 for temperature monitoring.</p> |
