| 摘要 |
In a vehicle-use cooling fan driving apparatus, a circuit is connected to a drain terminal of a driver transistor in order to sense a current of two motors which are connected in parallel. The circuit amplifies voltages of the terminal and source terminal of the driver transistor by the amount of the forward voltage of a diode. A power source is provided for supplying a current in order to amplify a voltage by the amount of forward voltage of the diode. The transistor prevents the amplified signal from being input to a microcomputer during an off-period of the transistor. A trouble-sensor compares the current value of the motors with a reference value with respect to a corresponding pulse width modulated signal so that trouble occurring in either of the two motors can be sensed so as to prevent an overheating of the motors.
|
