sequential LED RPM shift light, ?

Hi all,

I was wondering if anyone has ever come across any designs for a sequential LED RPM shift light.

I race cars, and ideally would love to have a 5 LED segment display which would begin to light up when a desired shift point is achieved. Each LED would light up as you approach the maximum RPM desired:

ie: LED1= 6250rpm LED2= 6500 rpm

etc... Most ignition systems put out a pulse that the tachometer picks up. (traditional coil systems with a distributor, multi coil/distributorless are different but I would assume still put out a pulse from the ECU/Ignition system module for the tach signal).

So, I guess I'd need a way to convert this pulse (and buffer it since the tach signal is usually high voltage, comes off of the negative side of the coil, I've been zapped before!) into a useable signal and then convert that signal to light up the LEDS. A pot would be necessary to "dial in" the desired RPM (which would be dialed when the engine is running at that rpm).

I've made a LED audio VU meter before, using a 10 segment LED driver, worked great (single IC, real basic). I guess I could use the same IC if I could convert that pulse to a voltage gain?

Anyhow, I think it would be interesting if someone here may have come across this before. If you've ever watched F1 or Rally events, you can see these nifty sequential LED shift lights.

Currently, my tachometer setup has an external shift light which lights up at a specified RPM (non sequential, just lights up when its time to shift!) made by Autometer (Sport Comp tach).

Thanks