| 摘要 |
PURPOSE:To prevent a vehicle from causing a fire due to runaway of a CPU, in a fuel injection control device for an automobile engine, by providing a pulse delay circuit for prolonging an injection pulse and an AND gate for delivering the injection pulse to an injector. CONSTITUTION:A micro-computer 1 receives signals from several sensors 6, and issues a fuel injection pulse signal (a). A pulse delay circuit 2 prolongs the injection pulse so that it has a predetermined pulse width. There is provided an AND gate 3 for taking a logic AND between an output (b) from the pulse delay circuit 2 and the injection pulse (a) to deliver an injection pulse (c) to a switching transistor 4 which is therefore turned on to energize a coil 5 in an injector for fuel injection. Even through a CPU runs away, the AND gate 3 is changed so that it has an L-level. Thus, it is possible to avoid setting the vehicle on fire due to leaving fuel blown out.
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