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I need to create a shorter pulse based on a trigger signal. Trigger signal has a duration between 1 to 10 ms and the desired output should be 0.5 ms.
To do the opposite (longer output pulse than input trigger) one can use a 555 as monostable (shown on the left) but what I need is the situation shown on the right. Is it possible to this with a 555 or with other monolitic IC?
Many thanks in advance!
If I understand your application correctly you can use an edge-triggered monostable multivibrator, for example 74LVC1G123.
As shown in the TI datasheet, figure 2, it is possible to have an output pulse shorter than the input pulse:
If the timing jitter (delay from the input to output) isn't too critical, you could also consider using a tiny microcontroller.
You could use a Monostable Pulse Generator like the LTC6993, which generates a programmable pulse width of 1 us to 33.6 s, which covers the 500 us that you need. Check pages 12 and 13 of the datasheet to program the pulse width.
When you pass the button trigger through a capacitor, and pull it up on both sides like this, you can quite easily generate a short pulse.
This way, when the button (red) is low for a longer time, the trigger level (green) will pull up instantly. This results in a short pulse and a desired output (blue). Of course, values should be changed when the timings are different.
