Power Pins

• VIN - this is the power pin. To power the board, give it the same power as the logic level of your microcontroller - e.g. for a 5V microcontroller like Arduino, use 5V.
• 5V - this is the 5V output from the charge-pump boosting regulator. It can provide 100mA continuous and 200mA peak.
• G - common ground for power and logic.

I2C Logic Pins

• 3CL - I2C clock pin for incoming 3V logic, connect to your microcontroller I2C clock line. It's meant as the 3V logic input, but you can use 3-5V logic. There is a 10K pullup on this pin.
• 3DA - I2C data pin for incoming 3V logic, connect to your microcontroller I2C data line. It's meant as the 3V logic input, but you can use 3-5V logic. There is a 10K pullup on this pin.
• 5CL - I2C clock pin for outputting 5V logic, connect to your microcontroller I2C clock line. It is level shifted to output 5V logic. There is a 10K pullup on this pin.
• 5DA - I2C data pin for outputting 5V logic, connect to your microcontroller I2C data line. It is level shifted to output 5V logic. There is a 10K pullup on this pin.
• STEMMA QT - These connectors allow you to connectors to dev boards with STEMMA QT connectors or to other things with various associated accessories.
  • The connector behind the arrows on the silk is for the 3V logic input
  • The connector being pointed to by the arrows on the silk is for the 5V logic output

Power LED and LED Jumper

• Power LED - In the lower right corner, below the STEMMA connector, on the front of the board, is the power LED, labeled on. It is a green LED.
• LED jumper - This jumper is located on the back of the board. Cut the trace on this jumper to cut power to the "on" LED.

Vi2c Jumpers

If you happen to be using a board that wants 5V power, but 3V logic I2C, there are jumpers located on the back, labeled Vi2C, that you can cut/solder to set the output logic level to unshifted 3V.

• 5V jumper - This jumper is located on the back of the board. Cut the trace on this jumper to set the output logic level to unshifted 3V.
• In jumper - This jumper is located on the back of the board. Solder this pad to the center Vi2c pad to set the output logic level to VIN.