Guides — howto
Posted by Henning Pedersen at
The micro:bit runs on 3V or 3,3 Volts from battery pack and 5V on USB. If you have a 5v power source and want to run the micro:bit, just solder the positive to the pad marked in red in this picture. You can verify this in advance by measuring the voltage on the pad when connected to USB. In addition you need a common ground (GND) to complete the circuit.