| 摘要 |
PURPOSE:To protect a transistor bridge circuit for supplying a current to a motor against heat. CONSTITUTION:When a temperature around a motor rises in a state that a current is supplied to the motor 1, potentials of a temperature sensor 38 having four diodes 38a-38d connected in series and a resistor 41 are raised, and hence an output signal of a comparator 37 is inverted, and low level signals are supplied to AND gates 11, 61. Accordingly, since transistors 6, 56 are turned OFF, supply of a current to the motor 1 is interrupted, and hence heat rise exceeding an allowable temperature of the transistor can be prevented. |
