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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