Hi,

Just thought I'd add my thoughts.

I have a product that fits to an automotive type end device, initially I used opto-isolators to monitor 12v inputs.
I found them to be uneccesary in the end, also they where prone to behaving differently in different pcb's for some reason..

Anyway I digress, my current production units all employ a 78L05 voltage regulator with a 100R resistor between the 5v output and the PIC's input.

This approach worked out cheaper and uses less board space than the opto-isolated version.

Hope this helps


Darryl...