>But I really didn't want to add inductors or
>caps on this board for space reasons.


The inductor is neither large or expensive, and the voltage is not a major 
safety issue.

When I first started out doing this, I found that just using current 
limiting resistors caused a tremendous difference in intensity depending 
whether the motor was running or not.

I didn't want to operate like that, so I changed to a boost converter-now I 
get the same intensity whether the motor is on or not.


>  And since it was for someone else, I
>didn't want to give him anything with high voltages.
>
>BTW, this circuit is also a quick project for someone else's custom truck 
>so I
>don't want to write any code for it right now


Neil, I think this is a non-PIC project unless you really want it to be 
fancy and/or massive overkill.

To some degree, my boost converter is also overkill.....but I really didn't 
like the idea of having the LED's go dim when I shut the car off.

I'm aware of lower power (and smaller physical size chips), but the boost 
regulator I had came in an 8 pin dip, so it was easy to build and a few 
extra milliamps supply current wasn't going to make much difference to a 
car battery. It's cheap and works well.

The LED's are amazingly bright and cheap too. I thought about using 
expensive single (mega buck) LEDs, but couldn't resist the cheaper and 
smaller LEDs in series.

Regards,

Art



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