• Arduino Uno
  • Laptop
  • 7.4V 2s LiPo Battery
  • Neewer 30A ESC


The LiPo powers the ESC while the Laptop USB powers the Arduino. If I unplug the USB from Arduino is loses power (obviously) and when I plug in the ESC to the arduino I get power again to the Arduino. I need the USB plugged in to receive Serial information from the laptop and I need pow+gnd plugged into the Arduino or else I get a lot of PWM noise rendering my ESC useless.

  • ESC is 5V
  • USB is 5V


This is my due diligence to not blowing anything up. What is the safest way to plug in power from both USB and the ESC? Same voltage, difference sources. Or can I just connect the grounds and call it good?


Connecting the grounds would work.

You could also connect the 7.2V lipo to the Vin pin on the UNO. The UNO will automatically switch from USB to Vin, if it's present.

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