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I'm trying to make a circuit (with no programmable circuits, only logic gates, flip flops and latches) that outputs a short impulsion each time it's input toggles from 0 to 1. Do you have any idea of how to do so?

TheCamel
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    "impulsion" could probably be replaced with "impulse", though that implies a theoretical pulse of zero duration, so it might be more useful to simply say "a short pulse" – Chris Stratton Dec 11 '11 at 17:23

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Please try to use normal english. I'm guessing "impulsion" is supposed to mean a single pulse?

If so, what you want is officially called a "monostable multivibrator" or more commonly a "one-shot". There are chips that do this directly, using a resistor and capacitor as the timing components to control the length of the resulting pulse. Check out the 74x121 and 74x122, for example.

Olin Lathrop
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  • Yes, sorry, by "impulsion" I meant a short single pulse. But, as far as I know, in a monostable multivibrator, when the input is kept high, the output does not switch back to the low state until the input does so... – TheCamel Dec 11 '11 at 14:34
  • @TheCamel - That depends on whether you monostable multivibrator is edge-triggered or level-triggered, as well as the multivibrator implementation. – Connor Wolf Dec 11 '11 at 14:39
  • @TheCamel: Did you check out the 74x121? That's exactly what it does. Only the *edge* of the input signal is relevant. For example, if you set it up to trigger on the rising edge, then you will get a fixed length pulse out each rising edge of the input signal *regardless of how long the input stays at the high level*. – Olin Lathrop Dec 11 '11 at 15:25