Condition Car Ignition Signal
This is galvanically isolated and will mimic the 12V signal at any* Vin.







simulate this circuit &ndash; Schematic created using CircuitLab

The camshaft position sensor (using any technology) outputs a pulse at EVERY firing.
CurrentWidthBetweenPulses = 1.0 / (RPM * NumberOfCylinders / 60.0)
RPM = ((1.0 / CurrentWidthBetweenPulses) * 60.0 / NumberOfCylinders)
RPM = ((1.0 / 0.015ms) * 60 / 8) = 500RPM
RPM = ((1.0 / 0.010ms) * 60 / 8) = 750RPM