CommunityForumWikiBlogLearn
Modules
Communications

Gravity: TCA9548A I2C Multiplexer Module

SKU: DFR0576

The Gravity: TCA9548A I2C Multiplexer Module perfect for users seeking to expand their I2C connections. It details the operating voltage, connector type, interface protocol, I2C clock rate, and port quantity, providing a comprehensive understanding of how the module can be utilized effectively. Additionally, it explains the dial switch settings for adjusting the module's default I2C address range, from 0x70 to 0x77. Readers will learn how to configure the module according to their project's needs, enabling them to manage multiple I2C devices through a single interface. This resource is ideal for hobbyists and professionals aiming to streamline their electronics projects with efficient I2C management.

Front of Gravity I2C Digital Multiplexer module with colored wires and connectors showing I2C communication interface.-DFRobot product sku:DFR0576 image.

Downloadable Resources

  • Docs
  • Tech Specs

    • Specification

    Parameter Value
    Operating Voltage 3.3~5.0V
    Connector Type PH2.0-4P
    Interface Level high 3.3V, low 0V
    Interface Protocol I2C(IIC)
    I2C Clock Rate 100K, 400K
    I2C Port Quantity 8
    Default I2C Address 0x70 (dial switches all to 0)
    I2C Address Range 0x70~0x77
    Dimension 32 * 32mm / 1.26 * 1.26in

    Pinout

    Num Label Description
    + VCC Power VCC(3.3~5V)
    - GND Power GND(0V)
    C SCL I2C Clock Line - SCL
    D SDA I2C Data Line - SDA
    R RESET RESET PIN, Active Low

    Dial Switch Description: As shown in the picture above, the dial switchs are all turned to the right(marked with '0') by default, at this time, A2,A1,A0 are all low level, so the default address of the multiplexer is 0x70. If the dial switchs are all turned to the left(marked with ‘1’), then A2,A1,A0 are all high level, and the address is 0x77. You can adjust the dial switchs as needed to set the address. You can set it from 0x70 to 0x77.

    FAQ

    • When a main controller is connected to two expansion modules at the same time, the data will interfere with each other.

      We have optimized this problem in our library file, you can disable the channel in the code, see the sample code in the link below for details:

      https://github.com/DFRobot/DFRobot_I2C_Multiplexer/blob/main/examples/multiSsd1306/multiSsd1306.ino

    • I was trying to connect 8 Qty SHT 85 humidity/temp I2C sensor to the multiplexer and then connect the multiplexer to NI 8451. However, I could never get more than 2 ports to work ie 0 and 1. I have tried switching the pullup resistors (required for SHT 85 sensor), I have tried switching the sensors around, even connected an external 5V power supply. Nothing seems to work. All the combinations of sensors seems to work with just ports 0 an 1. I am really frustrated, not sure what I am missing here.Any suggestions here?

      I have figured this out. Please include in the manual that in order to access port 0 of multiplexer we should "write data" = 00000001 (ie. 0x1 Hex) and to access port 5 of multiplexer, we should "write data" = 00100000 (ie 0x20 Hex). I was writing just 1,2,3,4,5,6,7,8 and hence only only 1, 2 were working as they were the correct hex numbers. Please include this in the documentation.

    Explore More Related Questions >

    Was this article helpful?

    TOP