Pulse Signal Reducer or pulse to current converter

Thread Starter

dfellars

Joined Mar 25, 2009
16
Hi Everyone, this is my first post and I am a bit of Noob.

I am looking to design a Pulse Signal Reducer or a pulse to current converter. The input signal is a 12v Hall Effect off an HEI Car Distributor. The Distributer pulses 3x per revolution so at 700 RPMs we are looking at 2100 pulses per minute. I would like to reduce that by a factor of 100. I thought that I might be able to uses a CMOS Decade Counter (CD4017) but I am not sure that can handle the pulse signal I am sending.

Project Scope:

I am attempting to build a flashing LED light system for my vehicle that flashes at a rate consistent with the RPMS (as the RPMs increase, so does the rate of the flash.) My thought was that if I can reduce the pulse to a reasonable rate I could simply wire the LEDs directly to the reducer.

Would this work or is there a more elegant design?

Thanks for your help.
 

Thread Starter

dfellars

Joined Mar 25, 2009
16
Hello,

Does it have to be 100 ?
May it be 128 ?

Take a look at the 4040 or 4060.
See datasheet.

Greetings,
Bertus
Yes, specificity is not a requirement.

Looked at the specs... the problem is the input voltage... I am relatively sure that the inpult signal is a full 12v (unless I am really showing my ignorance and missing something here.) I will test the line though to verify.
 

bertus

Joined Apr 5, 2008
22,278
Hello,

When you take the CD4040 (or HEF4040),
pin 11 (reset) is to ground.
Pin 10 is clock input.
Pin 2 divides the signal by 64
Pin 4 divides the signal by 128
Pin 13 divides the signal by 256
Pin 12 divides the signal by 512
(there are more outputs, see datasheet).

So you have different speeds at your service.

Greetings,
Bertus
 

thatoneguy

Joined Feb 19, 2009
6,359
Beyond about 20 flashes per second, an LED looks continually "on". For younger people, it goes to about 30/second.

Divide redline of car by 180, and you should arrive at the divider so that the LED is solid red (or whatever color you pick) at redline/yellowline.

For input, you could use an opto-isolator to keep any transient peaks from trashing your circuit.
 
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