I2C MUX 4 Click is a compact add-on board that contains a dual bidirectional translating switch dedicated for applications with I2C peripheral address conflicts. This board features the TCA9543APWR, a low voltage 2-channel I2C bus switch with interrupt logic from Texas Instruments. The controller SCL/SDA signals are directed to two downstream pairs, or channels, where either individual SCL/SDA channel or both channels can be selected by setting the programmable control register. It has two interrupts and a Reset input which allows the TCA9543A to recover from a situation where one of the downstream I2C buses is stuck in a low state. This Click board™ is suitable to work with I2C interfaces for applications such as fault isolation, address conflict, level translation, or broadcast communication.

I2C MUX 4 Click is supported by a mikroSDK compliant library, which includes functions that simplify software development.

I2C MUX 4 Click is based on the TCA9543APWR, a 2-channel, bidirectional translating I2C switch from Texas Instruments. The controller SCL/SDA signal pair is directed to two channels of peripheral devices SC0/SD0 - SC1/SD1 where either individual channel or both channels can be selected determined by the programmable control register. The TCA9543APWR supports interrupt signals for the controller to detect an interrupt that can result from any of the peripheral devices connected to the interrupt pins on the output I2C channel header. It features I2C control using a single 8-bit control register in which bits 1 and 0 control the enabling and disabling of the two switch channels of I2C data flow, it supports a reset function, hot insertion, and has all switch channels deselected during Power-Up.

This Click board™ includes a low dropout linear regulator AP7331 from Diodes Incorporated to provide the 2.45V supply voltage for the TCA9543APWR. When the TCA9543APWR is turned on for the first time or anytime the device needs to be reset by cycling the power supply, which means that the Power-On reset requirements must be followed to ensure the I2C bus logic is initialized properly. The TCA9543APWR can also be reset to its default conditions by using the Power-On reset feature in the event of a glitch or data corruption.

I2C MUX 4 Click communicates with MCU using the standard I2C 2-Wire interface that supports Standard-Mode (100 kHz) and Fast-Mode (400 kHz) operation. The TCA9543APWR generates a programmable interrupt signal routed on the INT pin of the mikroBUS™ used for the controller to detect an interrupt which can result from any of the peripheral devices connected to the output I2C channel pins. It also has two address pins that allow the choice of the least significant bit (LSB) of its I2C peripheral address which can be done by using the SMD jumper labeled as ADDR SEL, and a Reset function routed on the RST pin of the mikroBUS™ socket used to recover the TCA9543APWR from a bus-fault condition.

This Click board™ is designed to be operated with both 3.3V and 5V logic voltage levels that can be selected via VCC SEL jumper. This allows for both 3.3V and 5V capable MCUs to use the I2C communication lines properly.

• Interface: I²C
• Compatibility: mikroBUS™
• Dimensions: 28.6 x 25.4mm
• Input Voltage: 3.3V or 5V
• Supply Voltage: Min. -0.5V, Max. 7V
• Maximum Output Current: ±20mA
• Maximum Frequency: 400 kHz
• Maximum Power Dissipation: 400mW
• Operating Temperature Range: Min. -40°C, Max. +85°C

• Schematic
• AP7331 Datasheet
• TCA9543A Datasheet
• mikroSDK
• GitHub