Datasheet

There are 6 power pads available, equally spaced around the perimeter.

GND - there are 3 x Ground pads. They are all connected together, and are all the signal/power ground

connections

3.3V - there are two 3.3 Volt output pads. They are connected to the output of the onboard regulator. The

regulator can provide about 500mA max, but that includes all the built in parts too! So you should roughly budget

about 300mA available for your usage (450mA if you are not using the onboard NeoPixels)

Vout - there is one Voltage Output pad. This is a special power pad, it will be connected to

either

the USB

power or the battery input, whichever has the higher voltage. This output does not connect to the regulator so

you can draw as much current as your USB port / Battery can provide. There is a resettable fuse on this pin, so

you can draw about 500mA continuous, and 1 Amp peak before it will trip. If the fuse trips, just wait a minute and

it will automatically reset

If you want to connect chips, sensors, and low power electronics that requires 3.3V clean power, use the 3.3V pads.

If you want to connect servos, NeoPixels, DotStars or other high power electronics that are OK up to 5V, use the Vout

pad.

Input/Output Pads

Next we will cover the 8 GPIO (General Purpose Input Ouput) pins! For reference you may want to also check out the

datasheet-reference in the downloads section for the core ATSAMD21G18 pin. We picked pins that have

a lot

capabilities.

Common to all pads

All the GPIO pads can be used as digital inputs, digital outputs, for LEDs, buttons and switches. In addition, all can be

used as analog inputs (12-bit ADC). All but A0 can be used for hardware capacitive touch. All pads can also be used as

hardware interrupt inputs.