Circuit to Convert Random Spikes to Square Waves

This reminds me of early electronic rev counters. The width of the pulse from wherever (the points for example) varied. The solution was a monostable to make the pulses a fixed width.

Mike.

I don't know what you are really asking but a monostable Multivibrator comes to mind, a oneshot. It will put out a fixed pulse when it detects a spike. The pulse width should be less than the timing of the pulses.

The original spikes average 10mS. I constructed a standard LM555 monostable with 10uF and a 5K trimmer for the RC values.

http://www.ohmslawcalculator.com/555-monostable-calculator

It detects the spikes, makes them all the same amplitude, but the duty cycle at pin 3 is exactly the same as the spikes. What I wanted was for each cycle to stay "on" longer as per my previously uploaded diagram. Can anyone please suggest how to do this?

Tired of just lurking around on tis forum. Here is my thaught on how to resolve the issue - What I would have done.

You need two 3 major components: A custom integrator, that is able to reset itself, and a custom built mono stable flip-flop that has one extra input where voltage tetermines the holding time. Those two connects, and a back coupled inverted output (*) from the mono-stable flip flop to the reset of the integrator. * Probably need another monostable flip-flop that activates by negative flank to avoid integrator being disabled by reset input.

Oh my. Now I am in trouble. May need to reassess my needs to avoid a whole additional circuit board.

Can anyone offer a simpler, or compromise, design approach?

If the monostable doesn't work then you have something wrong. Are the spikes large enough to trigger it? Are they too large and you need a resistor divider?

Mike.

Start at the beginning. What are the amplitudes of the tallest and shortest spikes you want to capture. Note - the lower the short spike limit, the low-level noise triggers there will be.

ak