Prototyping with I2C has never been easier.
SparkFun's Qwiic Connect System uses 4-pin JST connectors to quickly interface development boards with sensors, LCDs, relays and more.
See Qwiic Products
Benefits of the Qwiic Connect System
The Qwiic Connect System is designed to keep your projects moving.
no soldering
Qwiic cables (4-pin JST) plug easily from development boards to sensors, shields, accessory boards and more, making easy work of setting up a new prototype.
polarized connector
There's no need to worry about accidentally swapping the SDA and SCL wires on your breadboard. The Qwiic connector is polarized so you know you’ll have it wired correctly every time, right from the start.
daisy chain-able
It’s time to leverage the power of the I2C bus! Most Qwiic boards will have two or more connectors on them, allowing multiple devices to be connected.
Qwiic Line of Products
Our Qwiic line of products has grown to include powerful development boards, helpful shields, a vast array of sensors and much more.
Development Boards
HATs and Shields
Sensors
Accessory Boards
Kits
Cables & Connectors
Connection Options
Interfacing any microcontroller or development board with an I2C port will work with the Qwiic Connect System. Currently, we offer four easy-to-use shields:
For devices like the popular Arduino Pro Mini 3.3V and Teensy we recommend either cutting a Qwiic cable in two, or using the Qwiic Breadboard Cable and soldering the cable to the four spots on your development board.
Arduino Pro Mini 3.3V using a 50mm Qwiic Cable and Teensy LC using a Qwiic Breadboard Cable
We found it made more sense to solder four wires into place, rather than add 24 male pins and 24 female pins onto a shield that costs a bit of money as well.
Need more than one connection? Consider soldering four wires to a Qwiic Adapter. – you’ll have two Qwiic ports for less than $1.
Frequently Asked Questions
Check below to answer any questions you may have about using the Qwiic Connect System.
How much power can I use?
The very conservative max current on a Qwiic cable is 226mA[1]. If you want to push it, 28AWG is good for up to 1.4A for chassis wiring “isolated, unbundled wire in free air, as per the Handbook of Electronic Tables and Formulas for American Wire Gauge.” We wouldn’t recommend pushing the cables to 1.4A, but hundreds of mA should be fine.
What’s the pinout again?
All Qwiic cables have the following color scheme and arrangement:
- Black = GND
- Red = 3.3V
- Blue = SDA
- Yellow = SCL
What about the INT pin?
We deliberately chose four conductors to increase usability of the interconnecting cables, minimize the cost of the connectors and limit the PCB footprint. All boards with extra pin options (such as interrupts, address selection, power save mode, etc.) will have those pins broken out to 0.1" holes, so the end user can add extra connections as needed.
How far can I run the Qwiic system?
I2C stands for inter-integrated circuit, and we’ve got a tutorial dedicated to it here. The bus was designed to communicate between ICs on a printed circuit board, so it wasn’t really designed to go long distances. That said, we’ve successfully communicated with sensors and boards via I2C over 1 meter (~4 ft).
The fastest and easiest way to extend the range of your I2C communication bus is to use the Differential I2C Breakout. The breakout uses NXP’s PCA9615 IC, which converts the two default I2C signals into four differential signals, two for SCL and two for SDA. The differential signals are sent over an Ethernet cable, which attaches to the breakout through the on-board RJ-45 connectors. The differential signaling allows the I2C signals to reach distances of up to 100ft while still maintaining their signal integrity!
Can I use Qwiic on my system?
Absolutely. We would be thrilled if you used a Qwiic connector on your board or product! You can use the name Qwiic without royalties or attribution.
The requirements to say that your board is Qwiic or Qwiic-Compatible:
- You must use a version of our registered Qwiic logo from the files provided. Download Qwiic Logos
- You must use the same style 4-pin connector, JST or equivalent; you may not use a 5-pin or a different size connector. This is to make all Qwiic boards and systems interoperable.
- Boards must be 3.3V. You may do an on-board buck or boost to get to a different voltage (1.8V or 5V, for example), but the board must have onboard translation circuitry to work at 3.3V.
- All cables must follow the same color scheme: black for GND, red for 3.3V, blue for SDA, yellow for SCL.
- For obvious compatibility reasons you must follow the same pinout: GND / 3.3V / SDA / SCL.
- You may have any number of Qwiic connectors on a board. We encourage having a second connector on input and output boards to support daisy-chaining, but it is not required.
What about my 5V board?
We may implement a DC buck/boost board in the future, but for now Qwiic only supports 3.3V boards. Currently over 90 percent of our I2C products are 3.3V, and the technology market is accelerating this trend.
How can I connect existing SparkFun I2C Boards?
What if you already have a handful of SparkFun sensors and parts? We have been putting our standard GND/VCC/SDA/SCL pinout on all our I2C boards for many years. This makes it possible to attach a Qwiic Adapter that will get your SparkFun I2C sensor or actuator onto the Qwiic system.
Here is the list of the boards that have the standard I2C pinout and will work with the Qwiic adapter board:
Projects, Tutorials & Hookup Guides
Whether you are looking for help hooking up hardware, or you're just looking for project inspiration, take a look below. We are always trying to expand our library of projects and tutorials, so check back often or fill out the form above to be notified of new content.
Build a Qwiic Jukebox that is Toddler Approved!
March 29, 2019
Follow this tutorial to build your own custom jukebox. Note, this is designed simple and tough for use primarily with toddlers. It's also a great introduction to SparkFun's Qwiic products!
GPS-RTK2 Hookup Guide
January 14, 2019
Get precision down to the diameter of a dime with the new ZED-F9P from Ublox.
Qwiic Transparent OLED HUD Hookup Guide
February 21, 2019
Learn how to connect that sweet transparent OLED.
SparkFun Qwiic AS3935 Lightning Detector Hookup Guide
April 18, 2019
Are you worried about the looming clouds in the distance, how far away is that storm exactly? Add lightning detection with the Qwiic AS3935 to your next weather station or your next bike ride!
Qwiic Scale Hookup Guide
April 11, 2019
Create your own digital scale quickly and easily using the Qwiic Scale!