PLL on crank angle sensor input

[G.Buckle]

At 12:41 4/03/97 -0800, you wrote:
>I am in the process of designing an microcontroller ignition system, and
>was wondering - 
>
>how common is it to use a PLL on the crank angle sensor input?
>does any one have a typical circuit design for this part of an efi
>system?


Have no answer, only a silly question..
Assumng the PLL you ask of is phase lock loop...
Why would you use it on a continuously varying freq input when PLL is used
to stabilise the freq of xtal controlled oscillators etc?

If it is to clean up the input, would a one shot m/v or Shmitt trigger be
better?

Or is it to stabilise the idle speed?

Like I said, I'm not sure what effect you hope for. If there is a good
reason to use PLL, a Wadley loop might also be worth considering.

;^)

Garry