M
Myron Samila
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
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
