Pulse generator on any Edge Detect

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RodSTAR

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Hello guys, I need a hopefully a single chip (or circuit if necesary) that meets the following requirements.

The following characteristics:
-voltaje: TTL (DC 3v3 / 5v)
-input: a pulse signal
-action: detect any high or low edge (of input pulse)
-output: a full pulse for each detected edge (of input pulse)
-other: the width of output pulse should be configurable example: example 1 uS (variable via pot)
-frequency: 50kHz at least

it sounds to me like a 555 can do that, really not sure. I'm a software guy, not an electronics yet.

I attached an image to make it clearer...
 

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thanks Ron,
wow! that looks like black magic... xP
So if I place a POT in place of R1 I can vary the high width time (period)??

PD: Should a 4070 also work instead? (CMOS Quad Exclusive-OR Gate)
 
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Yes, you can use a pot to vary the pulse width, and yes you can use a 4070. The 4070 has a high input impedance so you can use a larger resistor and a smaller capacitor for the same pulse as compared to the 74LS86.
 
very nice, thanks crutschow,
but, which formula should I use to get the values of capacitor and resistance to get a determined high time?
Example: 1uS
 
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very nice, thanks crutschow,
but, which formula should I use to get the values of capacitor and resistance to get a determined high time?
Example: 1uS
With a typical logic threshold for the 4070, the pulse width should be somewhat less that the RC time constant. Thus, for example with C= 100pF you would want R to be 10k ohm or a little higher.

Edit: A 50k ohm pot should give you plenty of adjustment range.
 
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