CANABLOX® 2:1 Channel I2C Bus Multiplexer (CX-MUX-S)

The CANABLOX® 2:1 Channel I2C Bus Multiplexer CX-MUX-S uses a TCA9546A bus switch that lets a single master communicate with 2 devices that share the same I²C address. CX-MUX-S uses the TCA9546A channels 0 and 1 (on the module A and B), making it a 2:1 I2C multiplexer. For example, two DS3231 RTC modules with the same address can be connected - one to each of the multiplexed channels - and accessed one at a time through the multiplexer. The "HOST" side connects only to the MCU and not to other I2C bus slaves. The only exception is the use of up to 3 multiplexers on the same "HOST" bus. The module is available in the "S" form factor (Single Slot) with the multiplexed bus channels A and B on top and the "HOST" channel on the bottom side.

Selectable I2C address: 0x71, 0x72, 0x74

Code example:
Download a demo sketch (tested with XIAO ESP32C6) that reads the time from 2 DS3231 RTCs (one on I2C-A and one on I2C-B) and sends both time stamps to the serial monitor.

>>> Find the documentation in the comments inside the demo code. <<<

PDF Datasheet:
Download TCA9546A PDF Datasheet

This is in the bag:
1 x CANABLOX® module
1 x male pin header 4-pin
1 x CANABLOX® I2C Cable 5cm

Note:
Through-Hole (TH) connectors, like the I2C pin header or screw terminals, are included but not factory assembled.

The CANABLOX® ecosystem

CANABLOX® is a modular, clean, stackable ecosystem that replaces the chaos of traditional prototyping with I2C-connected building blocks.

CANABLOX® is not just a hobby tool; it’s a stepping stone from prototype to finished product. With over 60 modules envisioned, from environmental sensors to serial bridges and audio applications, CANABLOX® becomes a platform, not just a product.

Every CANABLOX® module connects directly to a sturdy baseplate or standardized cables, letting you build solid, real-world systems - without the clutter.

All modules use standardized CANABLOX® slot sizes and can be connected either through 4-pin JST-SH cables (compatible with Qwiic and Stemma QT) or by direct mounting onto the baseplate with headers. Every baseplate includes I2C headers (not assembled) and mounting hardware.

Baseplate sizes:

Layout examples: