SparkFun QwiicBus Kit

Standard I²C communication quickly fails over long distances due to noise and signal drop, which can be incredibly frustrating when wiring a large sensor network or an autonomous robot. The SparkFun QwiicBus Kit solves that problem out of the box by letting you run I²C signals over standard Ethernet cables! Inside this, kit you'll find two EndPoints to start and finish your chain, one MidPoint to drop a sensor in the middle, and two 3-foot Ethernet cables to connect each board to the others.

Differential Signalling & Drop-In Expansion

The QwiicBus system's secret is the NXP PCA9615 IC, which converts standard I²C signals into four differential signals (two for SCL and two for SDA). This allows your data to travel cleanly over long Ethernet cables without requiring you to packetize the communication into complex protocols like RS-485 or 1-Wire packets. You just plug everything in and write your code exactly as you normally would. These differential signals are then sent over a standard Ethernet cable via the onboard RJ-45 connectors, which can easily reach up to 100 feet while resisting noise and maintaining signal integrity.

Long-Range Qwiic

Because the EndPoint is fully Qwiic-enabled, you can set up a sensor network in your home or run data lines across an autonomous vehicle with no soldering required! And just to make sure your data survives the journey, the QwiicBus system is built for reliability:

• Massive Range: Differential signalling lets your native I²C signals reach up to 100 feet while maintaining clear signal integrity.
• Proven Performance: In our extreme stress tests utilising two EndPoints and four MidPoints, all eight connected Qwiic devices operated successfully with almost zero signal loss.
• Expandable Architecture: The EndPoints serve as the start and end of your bus, while the MidPoint lets you easily add I²C sensor connections wherever you need them along the cable run.
• High-Power Delivery: The included MidPoint features a built-in LMR33630 buck regulator that can source high current to power heavy-duty devices attached mid-network.

Whether you have a robot with multiple I²C devices throughout it, a sensor network project with multiple sensors over a large area, or other I²C projects you can think of that require a wired signal transmission over long distances, QwiicBus makes that communication a breeze!

• QwiicBus General Documentation:
  • Hookup Guide
  • Datasheet (PCA9615)
  • Building a Custom Solution for Farming
  • Qwiic Info Page
• QwiicBus EndPoint Documentation:
  • Schematic
  • Eagle Files
  • Dimensional Drawing
  • Hardware GitHub Repository
• QwiicBus MidPoint Documentation:
  • Schematic
  • Eagle Files
  • Dimensional Drawing
  • Datasheet (LMR33630)
  • Hardware GitHub Repository