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im trying create a CDI/TCI unit for my Suzuki Bandit GSF400. i need some help for VR sensor signal conditioning section.

this is the disc that generate the pulse signal.

Signal Disc

i have found this image from Megasquirt Support Forum. and actually this is the same signal that generate in my bike also.

scope trace from trigger, and the processed signals

the first signal is the processed signal, and the second one is generated by the VR sensor.

i need a help to create a circuit to process the VR sensor signal to the above signal.

i believe this processing is not done by using zero crossing detector circuit, because the signal disc teeth sizes are efferent.

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Use a comparator with hysterisis.

Hysterisis allows it to trigger in one direction on an input pulse but when that input pulse returns to "neutral" (or midrail or 0V whatever it is), the output of the comparator remains triggered until an opposite input pulse comes along and takes it past the opposite hysterisis threshold. Then the comparator output toggles to the other direction.

What I'm describing is reversing the effect of a high pass filter. Here's what a high pass filter does to a square wave: -

enter image description here

All my suggestion does is use thresholds to recreate the square wave from the differentiated signal caused by what is likely to be an inductive proximity sensor (they tend to differentiate the magnetic fields and produce this waveform). Here's what the differentiated pulse looks like superimposed on the original sq wave: -

enter image description here

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