The input power to the board goes through a 5 volt regulator. It is ideal to supply the board with
between 6 and 15 volts of DC power that is capable of supplying at least 150 milliamperes of
The servos can either be powered by internal power, or by the external servo power connector.
To run them off of external power, remove the internal servo power jumper like shown below.
Then connect a second power supply to the “External Servo Power Connector”. To run off of
internal power, connect the “Internal Servo Power” jumper and disconnect any external servo
Warning: powering the servos from internal power means that if the servos require more
current than is available to power both servos and the processor, then the processor may
reset or fail to operate at all. Running three or more servos off of internal power will likely not
succeed. Be careful what voltage you supply to the External Servo Power input since it will not go through a regulator. Most servos require 5 volts, but some standard servos can still work at up to 7 or 8 volts.