7Semi- TCA9543A I2C Multiplexer Board – 2-Channel I2C Bus Switch

The 7SEMI TCA9543A I2C MUX Board is a low-voltage, 2-channel I²C bus switch designed for applications where address conflicts or I²C expansion is needed. Built around Texas Instruments’ TCA9543A, this board allows a single I2C master to control multiple slave buses with independent interrupts and reset support.

With support for 1.65V–5.5V logic, voltage-level translation, and hot-swap tolerance, this compact breakout is ideal for sensor networks, multi-sensor gateways, debugging tools, and industrial monitoring.

Key Features 

• 2-Channel Bidirectional I²C Switching

• Voltage Translation between 1.8V, 2.5V, 3.3V, and 5V buses

• I²C Controlled Channel Selection with dedicated address bits

• Interrupt Support: Two independent interrupt inputs (INT0, INT1) and one combined output

• RESET Input to recover from stuck bus scenarios

• Compatible with SMBus and Standard/Fast I2C (up to 400kHz)

• 5.5V-Tolerant Inputs with low standby current

• Qwiic-Compatible Header Pins

• Operating Voltage: 1.65V – 5.5V

Applications 

• Connect multiple I²C devices with the same address on a single controller

• Interface with multi-sensor arrays in smart farming, weather stations, or industrial IoT

•  Perform I²C bus isolation and debugging during development and testing

• Control separate smart home or building automation zones with identical sensors

• Expand I²C peripherals in robots, drones, and embedded systems

• Switch between I²C-controlled displays, actuators, and EEPROM banks

What’s Included

• 1x TCA9543A I2C MUX Board

Resources

• TCA9543A Datasheet