Expansion Board PCA9548 8CH to 8 I2C Multiplexer

AED 18.90



The PCA9548A serves as an eight-channel bidirectional I2C multiplexer, facilitating control of eight distinct I2C devices using a single host I2C bus. To integrate I2C sensors, simply connect them to the SC/SD multiplexed buses. Visualize the PCA9548A as a pivotal link between your Arduino and eight independent I2C buses. On one side, a solitary bus is connected to your Arduino. On the flip side, the PCA9548A branches out into eight I2C buses, with only one of these accessible to the Arduino at any given time. This configuration allows seamless management of multiple I2C devices through the convenience of a singular I2C bus connection.



  • Interface: I2C IIC: The device uses the I2C (Inter-Integrated Circuit) or IIC (I2C Inter-Integrated Circuit) communication protocol. 
  • Chip: TCA9548A: The multiplexer chip utilized in the device is the TCA9548A. This chip is designed for I2C bus expansion, allowing multiple devices with the same I2C address to be controlled individually.
  • Selectable I2C Address: 0x70-0x77: The device supports multiple selectable I2C addresses ranging from 0x70 to 0x77. The specific address can be configured using the A0, A1, and A2 pins. This flexibility is crucial when using multiple devices on the same I2C bus.
  • Working Voltage: 1.65-5.5V: The device operates within a voltage range of 1.65V to 5.5V. This range provides compatibility with various microcontrollers and ensures flexibility in different electronic applications.
  • Max Clock Frequency: 400 kHz: The maximum clock frequency supported by the device is 400 kHz. This defines the speed at which data is transmitted between the microcontroller and the multiplexer chip over the I2C bus. Higher frequencies allow for faster data transfer.


Pinout :


Vin Power pin for the sensor chip (3-5 VDC). Connect to the microcontroller's logic level (e.g., 5V for a 5V micro like Arduino)
GND Common ground for power and logic
SCL I2C clock pin for the chip. Connect to the microcontroller's I2C clock line
SDA I2C data pin for the chip. Connect to microcontroller's I2C data line
RST Reset pin for resetting the multiplexer chip. Pulled high by default, connect to ground to reset
A0-A2 Address selection pins for the multiplexer. The default address is 0x70. Connect to Vin to set the address to 0x71-0x77. A0 is the least significant bit, A1 is the 2nd least significant bit, and A2 is the 3rd least significant bit
SDx Multiplexed I2C data pins (SD0 to SD7). Each set is a separate I2C bus. No pull-ups are installed, so add external pull-ups if necessary. 5V is compliant even with a 3.3V Vin.
SCx Multiplexed I2C clock pins (SC0 to SC7). Correspond to the SDx pins. No pull-ups installed; add external pull-ups if needed. 5V compliant even with a 3.3V Vin.


Wiring with an Arduino board:

Connection Description
VIN Connect to 5V (or 3.3V)
GND Connect to ground
SDA Connect to A4 pin
SCL Connect to A5 pin

After connecting the PCA9548A multiplexer to the microcontroller using these configurations, sensors can be easily integrated by connecting them to the SCn / SDn pairs, where 'n' represents the channel number (e.g., SC1/SD1 for the first channel).