| 摘要 |
The invention relates to a method for generating a switching or control signal after a period that can be predetermined. At the beginning of timing a voltage (U) is applied to an inductivity (L) that serves as a time function element. If the current (I) passing through the inductivity (L) exceeds a threshold value that can be predetermined, a current threshold detector (ID) emits the switching or control signal. In an electronic ignition system for internal combustion engines the ignition coil (L, PW, SW) does not only generate an ignition voltage but represents also a time function element for a timer system (UD1, UD2, LS) that cuts off the current (I) passing through the primary winding (PW) of the ignition coil (L) after a period that can be predetermined. The current (I) is cut off on the basis of a differential function dI/dt that is chosen so that the ignition voltage induced at the ignition coil (L) does not suffice to generate an ignition spark on the ignition plugs.
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