Hello Everyone,
I am trying to figure out how to control an input voltage. I am building a I/O controller that will take a range of voltages (5-30vdc) and of course
use that to trigger an input on the arduino.
I have built it and it works but I am concerned about the resistor getting too hot. It is a 4n25 opto, with a 2.7k resistor inline for the led input on the
opto.
My thought is that it simply cannot dissipate the heat properly. Otherwise it works great.
My question is, is there some type of zener or other voltage limiting device that I can control the voltage and clamp it so that the large range of
inputs do not burn the resistors up?
Any suggestions are very much appreciated.