Reading 28v into my arduino input

Development Boards Arduino
1

Hello, I am looking for a breakout board that will allow my arduino to accept a 5v signal on an input when the device I am interested in sends a voltage of 28v. I have been searching for optocouplers and level shifters etc, but I can’t seem to find anything that will take in a voltage of up to 30v and output 5v. I am not an expert, so I would really like a pre-packaged isolator that I can simply wire up between the 28v source and my arduino. I don’t want to have to make this from scratch if I can avoid it. Does sparkfun make such a thing?

Thanks for your help!

2

We don’t have anything, but you can build your own voltage divider circuit with 2 resistors that makes a 0 to 30 volt input into a 0 to 5 volt output.

The tutorials in the links below will show you how to build one.

  • - https://learn.sparkfun.com/tutorials/vo … viders/all

  • - [https://ohmslawcalculator.com/voltage-d ... calculator](https://ohmslawcalculator.com/voltage-divider-calculator)
    • 3

    Thanks for your help! Maybe what I was thinking was overkill.

    Best wishes

    4

    What are you using this signal for? If you want to supply power from the 28VDC line, then a DC-DC converter like a RECOM would do the trick for under $2. If this is a digital signal, then a level shifter could be used (or use 2 MOSFETS, as in http://cdn.sparkfun.com/tutorialimages/ … n97055.pdf). If you want to measure the signal using Arduino analog pins, then the voltage dividers mentioned above are the way to go.

    Also, if you want to measure the voltage, you can use an INA228, INA230, INA231, INA260, INA2331 to measure not only the voltage but also the current.