| 摘要 |
An injector drive circuit for driving an injector having a valve opened and closed according to a pulse signal with the pulse duration thereof corresponding to the quantity of fuel supplied to the engine. The injector drive circuit comprises a current supply power transistor connected to an injector coil. According to an electric pulse signal from a fuel injection control circuit, a first current control section causes base current to flow into the power transistor for causing a peak current through the injector coil. When a predetermined peak current is detected, the base current supplied by the first current control section is cut off. From this instant till the disappearence of the electric pulse signal, a second current control section, which supplies base current to the power transistor only when the current supplied from the power transistor to the injector coil becomes lower than a working current level, supplies in effect the working current through the power transistor to the injector.
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