# Adafruit DS2484 I2C to 1-Wire Bus Adapter Breakout ## Overview ![](https://cdn-learn.adafruit.com/assets/assets/000/130/700/medium800/adafruit_products_5976-06.jpg?1718303392) By customer request, this is a [DS2484](https://www.digikey.com/short/5f85v4tf) Stemma QT board that uses a I2C-to-1-Wire controller chip, with electrostatic (ESD) protection and support for split supplies. You can easily connect it to an existing I2C bus and then use the screw terminals to attach multiple DS18B20 temperature sensors, or pair it with our [1-Wire chaining breakouts](https://www.adafruit.com/product/5971) for fancier experimentation. ![](https://cdn-learn.adafruit.com/assets/assets/000/130/701/medium800/adafruit_products_5976-05.jpg?1718303430) You're probably familiar with the 'top three' electronics protocols: I2C, SPI and UART. Perhaps you're aware of a fourth one, [called "1-Wire" which was invented by Dallas Semiconductor](https://www.analog.com/en/resources/technical-articles/guide-to-1wire-communication.html) (which became Maxim, which became Analog Devices). As you may expect, this protocol uses a single data wire plus a ground wire (and an optional power wire) to connect to any number of sensors or memory chips that all share the same bus. ![](https://cdn-learn.adafruit.com/assets/assets/000/130/702/medium800/adafruit_products_5976-02.jpg?1718303466) In theory, there's a lot of different 1-Wire devices out there, but in reality almost everyone uses 1-Wire for DS18B20 temperature sensors. The long wire lengths and ease of 'chaining' by sharing a single bus wire makes it perfectly fine for this purpose. You can bit-bang a 1-Wire interface on most microcontrollers, and some SBCs like [Raspberry Pi have kernel module support](https://learn.adafruit.com/adafruits-raspberry-pi-lesson-11-ds18b20-temperature-sensing). But there are lots of chips or firmware stacks without 1-Wire capability, or maybe you want to use 1-Wire devices on your desktop computer or other SBC with I2C. ![](https://cdn-learn.adafruit.com/assets/assets/000/130/703/medium800/adafruit_products_5976-03.jpg?1718303500) To get you going fast, we spun up a custom-made PCB in the [**STEMMA QT** form factor](https://www.adafruit.com/?q=stemma%20qt%20sensor "STEMMA QT form factor"), making it easy to interface with. The [STEMMA QT connectors](https://learn.adafruit.com/introducing-adafruit-stemma-qt/what-is-stemma-qt) on either side are compatible with the [SparkFun Qwiic](https://www.sparkfun.com/qwiic) I2C connectors. This allows you to make solderless connections between your development board and the DS2484 or to chain it with a wide range of other sensors and accessories using a [**compatible cable**](https://www.adafruit.com/?q=stemma%20qt%20cable). ![](https://cdn-learn.adafruit.com/assets/assets/000/130/704/medium800/adafruit_products_5976-04.jpg?1718303559) You can power the board directly from the STEMMA QT cable, whether it is 3V or 5V. If you want a different voltage on the 1-Wire power pin, cut the onboard trace and you can inject the voltage at the terminal block. - [Next Page](https://learn.adafruit.com/adafruit-ds2484-i2c-to-1-wire-bus-adapter-breakout/pinouts.md) ## Primary Products ### Adafruit DS2484 I2C to 1-Wire Bus Adapter Breakout [Adafruit DS2484 I2C to 1-Wire Bus Adapter Breakout](https://www.adafruit.com/product/5976) By customer request, this is a [DS2484](https://www.digikey.com/short/5f85v4tf) Stemma QT board that uses a I2C-to-1W controller chip, with ESD protection and support for split supplies. You can easily connect it to an existing I2C bus and then use the screw terminals... In Stock [Buy Now](https://www.adafruit.com/product/5976) [Related Guides to the Product](https://learn.adafruit.com/products/5976/guides) ## Featured Products ### DS18B20 Digital temperature sensor + extras [DS18B20 Digital temperature sensor + extras](https://www.adafruit.com/product/374) These 1-wire digital temperature sensors are fairly precise (±0.5°C over much of the range) and can give up to 12 bits of precision from the onboard digital-to-analog converter. They work great with any microcontroller using a single digital pin, and you can even connect multiple... In Stock [Buy Now](https://www.adafruit.com/product/374) [Related Guides to the Product](https://learn.adafruit.com/products/374/guides) ### Waterproof 1-Wire DS18B20 Digital temperature sensor [Waterproof 1-Wire DS18B20 Digital temperature sensor](https://www.adafruit.com/product/381) This is a pre-wired and waterproofed (with heat shrink) version of a 1 Wire DS18B20 sensor. Handy for when you need to measure something far away, or in wet conditions. While the sensor is good up to 125°C the cable is jacketed in PVC so we suggest keeping it under 100°C. Because they... In Stock [Buy Now](https://www.adafruit.com/product/381) [Related Guides to the Product](https://learn.adafruit.com/products/381/guides) ### STEMMA QT / Qwiic JST SH 4-Pin Cable - 50mm Long [STEMMA QT / Qwiic JST SH 4-Pin Cable - 50mm Long](https://www.adafruit.com/product/4399) This 4-wire cable is 50mm / 1.9" long and fitted with JST SH female 4-pin connectors on both ends. Compared with the chunkier JST PH these are 1mm pitch instead of 2mm, but still have a nice latching feel, while being easy to insert and remove. Out of Stock [Buy Now](https://www.adafruit.com/product/4399) [Related Guides to the Product](https://learn.adafruit.com/products/4399/guides) ### STEMMA QT / Qwiic JST SH 4-pin Cable with Premium Female Sockets [STEMMA QT / Qwiic JST SH 4-pin Cable with Premium Female Sockets](https://www.adafruit.com/product/4397) This 4-wire cable is a little over 150mm / 6" long and fitted with JST-SH female 4-pin connectors on one end and premium female headers on the other. Compared with the chunkier JST-PH these are 1mm pitch instead of 2mm, but still have a nice latching feel, while being easy to insert and... In Stock [Buy Now](https://www.adafruit.com/product/4397) [Related Guides to the Product](https://learn.adafruit.com/products/4397/guides) ### STEMMA QT / Qwiic JST SH 4-pin to Premium Male Headers Cable [STEMMA QT / Qwiic JST SH 4-pin to Premium Male Headers Cable](https://www.adafruit.com/product/4209) This 4-wire cable is a little over 150mm / 6" long and fitted with JST-SH female 4-pin connectors on one end and premium Dupont male headers on the other. Compared with the chunkier JST-PH these are 1mm pitch instead of 2mm, but still have a nice latching feel, while being easy to insert... Out of Stock [Buy Now](https://www.adafruit.com/product/4209) [Related Guides to the Product](https://learn.adafruit.com/products/4209/guides) ### JST SH 4-pin Cable with Alligator Clips - STEMMA QT / Qwiic [JST SH 4-pin Cable with Alligator Clips - STEMMA QT / Qwiic](https://www.adafruit.com/product/4398) This cable will make it super easy to use our plug-and-play STEMMA QT boards with boards like Circuit Playground. On one end you get a Qwiic / STEMMA QT connector (technically known as a JST SH 4-pin plug)  into 4 individual wires with grippy alligator clips. We're carrying these to... Out of Stock [Buy Now](https://www.adafruit.com/product/4398) [Related Guides to the Product](https://learn.adafruit.com/products/4398/guides) ## Related Guides - [Adafruit 7-Segment LED FeatherWings](https://learn.adafruit.com/adafruit-7-segment-led-featherwings.md) - [Remote Control Tree Ornament with Circuit Playground Express](https://learn.adafruit.com/remote-control-tree-ornament-with-circuit-playground-express.md) - [PyBadger Event Badge](https://learn.adafruit.com/pybadger-event-badge.md) - [Adafruit I2C Quad Rotary Encoder Breakout](https://learn.adafruit.com/adafruit-i2c-quad-rotary-encoder-breakout.md) - [PyPortal Trivia Time with the Open Trivia Database](https://learn.adafruit.com/pyportal-trivia-time-open-trivia-database.md) - [NeoPixel Infinity Mirror Coaster](https://learn.adafruit.com/infinity-mirror-coaster.md) - [Green Goblin Pumpkin CPB Ornament](https://learn.adafruit.com/green-goblin-pumpkin-cpb-ornament.md) - [LoRa Signal Bridge with the Feather RP2040 RFM ](https://learn.adafruit.com/lora-signal-bridge-with-the-feather-rp2040-rfm.md) - [CircuitPython Hardware: ILI9341 TFT & FeatherWing](https://learn.adafruit.com/micropython-hardware-ili9341-tft-and-featherwing.md) - [Adafruit PiCowbell CAN Bus for Pico](https://learn.adafruit.com/adafruit-picowbell-can-bus-for-pico.md) - [Arcade Coin-Op](https://learn.adafruit.com/arcade-coin-op.md) - [Adafruit ICM20649 Wide-Range 6-DoF IMU Accelerometer and Gyro](https://learn.adafruit.com/adafruit-icm20649-wide-range-6-dof-imu-accelerometer-and-gyro.md) - [MagTag Weekly Showtimes Event Notifier](https://learn.adafruit.com/magtag-weekly-event-showtimes-display.md) - [Adafruit microSD Card BFF](https://learn.adafruit.com/adafruit-microsd-card-bff.md) - [Adafruit IO Basics: AirLift](https://learn.adafruit.com/adafruit-io-basics-airlift.md)