Battery question for powering arduino

Hello, I am new to this site so I apologize if this is posted in the wrong forum.

I am doing a school project that involves an Arduino Uno working with a relay to control a linear actuator.

We have a 12 V 1600 mAh battery to power the actuator, but the electrical technician at our school said we need a separate power source for the arduino because the 12 V one would short the board. I don't know much about batteries, so I have been struggling to find something to power the device.

I saw a link on amazon titled 9V/5V battery adapter for arduino (link: and was wondering if using this device with a 9V battery would work for powering the arduino? Does the 9V/5V imply from the 9 volt battery it will provide 5 volts? Is a 9V too much? Any suggestions on how to power this device are greatly appreciated as I am a mechanical engineer and therefore am very electrically challenged.


Let's see your proposed schematic for this project.

12V can be used to power an Arduino (UNO for example) but there will be limitations to the amount of current that can be safely taken form it.

You can get a buck converter (lots on eBay) that can lower the 12V down to a more reasonable level.
7V if you power the Arduino through the power jack OR 5V if you power the Arduino through the 5V header pin.

One example:

Hopefully this is what you meant by schematic. I was unsure if you meant the wiring to connect it or not. Basically there is going to be a force sensing resistor that will connect to the arduino, the arduino will be connected to our 2 module relay, and connected to the relay is both the 12 V battery source and our linear actuator. The highlighted portion of the schematic is what our electrical technician recommended and we are exploring, but if it can be done with the 12 V powering the entire system that would be great, just wasn’t sure if the battery could provide 12 V to the actuator as well as 5 to the board.

Let me know if this wasn’t what you meant by schematic or if you need any more information.

Thanks for your help



If that’s all you have in the cct., 12v into the Arduino will probably be okay.

Touch the voltage regulator on the Arduino with your finger to make sure it is not too hot.


Use a buck converter.