By customer request, this is a DS2484 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 to attach multiple DS18B20’s, or pair it with our 1-Wire chaining breakouts for fancier experimentation.
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 (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.
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 1-Wire on most microcontrollers, and some SBCs like Raspberry Pi have kernel module support. But 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.
To get you going fast, we spun up a custom-made PCB in theSTEMMA QT form factor, making it easy to interface with. The STEMMA QT connectors on either side are compatible with the SparkFun 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.
You can power the board directly from the STEMMA QT cable, whether 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.
Adafruit publishes a wide range of writing and video content, including interviews and reporting on the maker market and the wider technology world. Our standards page is intended as a guide to best practices that Adafruit uses, as well as an outline of the ethical standards Adafruit aspires to. While Adafruit is not an independent journalistic institution, Adafruit strives to be a fair, informative, and positive voice within the community – check it out here: adafruit.com/editorialstandards
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.
Have an amazing project to share? The Electronics Show and Tell is every Wednesday at 7:30pm ET! To join, head over to YouTube and check out the show’s live chat and our Discord!
