Knowledge Base

The AB Electronics UK Knowledge Base provides support solutions, tutorials and troubleshooting guides.

1 Wire Pi

Created 11/05/2016 | 1 Wire Pi expansion board legacy information

This item has been replaced with the 1 Wire Pi Plus.

  • 1-Wire® to I2C host interface with ESD protection diode.
  • Stackable with other Raspberry Pi accessory boards.
  • Buffered 5V I2C port.
  • External 5V power input for 1-Wire® interface.

The 1 Wire Pi from AB Electronics UK is a communication board supporting the 1-Wire® protocol.  A 5V buffered I2C port is also provided on the board.

The 1-Wire® port is based around a DS2482-100 I2C to 1-Wire® bridge device.  The DS2482-100 provides bi-directional protocol conversion between the I2C port on the Raspberry Pi and any attached 1-Wire® slave devices.  An ESD Protection Diode is used to protect the 1 Wire Pi and Raspberry Pi from electrostatic spikes on the 1-Wire® port.  Connections to the 1-Wire® port can be made through the RJ-12 socket or the solder points on the PCB.  See our KB page for configuring and using the 1-Wire® port on your Raspberry Pi.

A 5V input port is also provided allowing you to use an external power supply on the 1-Wire® interface, reducing the load on the Raspberry Pi.  If you choose to use the external 5V input please remove the jumper on the board to isolate the Raspberry Pi 5V bus.

A detailed tutorial has been written by Jack Creasey, author of Raspberry Pi Essentials,for the setup of OWFS with the 1 Wire Pi and 1 Wire Plus boards. View the tutorial.


1-Wire Pi Datasheet

DS2482S (1-Wire Interface)

Input Ratings & Specifications

Vdd (5V input pin): 5.0V

Maximum current on 1-Wire pins: ±20 mA

I2C SDA/SCL voltage: 5.0 V

I2C port current: 100 mA


Click to download
Click to download schematic PDF.

Mechanical Drawings

Mechanical Drawing

Click image to enlarge

Sample Code

The Quick2wire lib from allows easy access to the I2C port via Python.

Configuring and using the 1-Wire® port on your Raspberry Pi


Note: documents in Portable Document Format (PDF) require Adobe Acrobat Reader 5.0 or higher to view, download Adobe Acrobat Reader or other PDF reading software for your computer or mobile device.