# Multiplexer module, I2C, 8 channels, PCA9548, 3.3-5V

> I2C multiplexer module with 8 channels based on the PCA9548 chip, allowing up to 8 sensors or modules with the same I2C address to be connected to a single microcontroller. Own address configurable between 0x70-0x77 via pins A0-A2, operates at 2.3-5V, logic level 3.3-5V without a level shifter, I2C frequency up to 400kHz. Compatible with Arduino and other development boards.

- Page: https://sigmanortec.ro/en/multiplexer-module-i2c-8-channels-pca9548-33-5v
- Price: 7.44 RON
- Availability: In stock; 1-2 zile
- Reference: 9564 · EAN: 5945849696951
- Category: Mechatronics and IoT > Sensors and Modules > Expansion Module
- Specifications: Supply Voltage: 3.3; Maximum Input Voltage: 5; Input Voltage Type: “DC” in Romanian can mean **“de ce”**, which translates to **“why”** in English.; Model: PCA9548
- Package (shipping data): 0.005 kg
- Updated: 2026-09-14
- Shop: [Sigmanortec.ro](https://sigmanortec.ro/en/llms.txt)
- Prices: RON, VAT included; prices and stock as of 2026-10-22 03:39 (Europe/Bucharest)

## Description

It extends the I2C bus and eliminates address conflicts, allowing up to 8 identical sensors or modules to be connected to the same microcontroller. It has 8 channels selectable by sending a byte, configurable own address 0x70-0x77 via A0-A2, operates at 2.3-5V with 3.3-5V logic without level shifter, supports up to 400kHz for quick integration with Arduino and other boards.
Multiplexer module, compatible with Arduino and other development boards, allows connection of up to 8 devices on the same I2C address. This happens when you have multiple sensors using the same I2C address, making it impossible to use them simultaneously.
The multiplexer itself is at I2C address 0x70 (configurable between 0x70 and 0x77) and works by sending a single byte to the multiplexer specifying the desired channel. The multiplexer communicates with the microcontroller via I2C, and the microcontroller selects which port on the multiplexer will be used. Theoretically, up to 8 multiplexer modules can be used, each with its own address between 0x70 and 0x77, each connected to 8 sensors, for a total of 64 I2C sensors on the same microcontroller.
This module is compatible with 3.3V and 5V logic levels, without the need for a logic level translator.
Specifications:
Supply voltage: 2.3 - 5VDC
Frequency: 0-400kHz
I2C address: Selectable, between 0x70 and 0x77
Number of available channels: 8 buses
Usage:
The address used is set by configuring pins A0, A1, and A2 as follows:
A0
A1
A2
I2C ADDRESS
LOW
0X70
HIGH
LOW
0X71
LOW
HIGH
LOW
0X72
HIGH
LOW
0X73
LOW
HIGH
0X74
HIGH
LOW
HIGH
0X75
LOW
HIGH
0X76
HIGH
0X77
Setting to LOW is done by connecting the respective pin to GND, setting to HIGH by connecting to the module's supply voltage (VCC).
To select an I2C bus for writing/reading, it is necessary to send a byte to the multiplexer with the desired output port (in numeric format, from 0 to 7).
Example of port selection with Arduino:
void TCA9548A(uint8_t bus){
Wire.beginTransmission(0x70); // The TCA9548A address is 0x70
Wire.write(1 << bus); // send byte to selected bus
Wire.endTransmission();
Serial.print(bus);
}
Afterwards, it is sufficient to call the function and send as an argument the port number you want to control before sending I2C commands. For example, to control the device connected to bus number 3, call the following line before other I2C commands. Ports start at 0.
TCA9548A(2);
Pinout:
Pin
Description
VIN
Supplies power to the multiplexer
GND
Connected to GND
SDA
Connected to the main microcontroller's SDA pin
SCL
Connected to the main microcontroller's SCL pin
RST
RST with pin LOW - can be used to reset the multiplexer
A0
Selects the multiplexer I2C address - connected to GND or VCC
A1
Selects the multiplexer I2C address - connected to GND or VCC
A2
Selects the multiplexer I2C address - connected to GND or VCC
SD0
SDA for channel 0
SC0
SCL for channel 0
SD1
SDA for channel 1
SC1
SCL for channel 1
SD2
SDA for channel 2
SC2
SCL for channel 2
SD3
SDA for channel 3
SC3
SCL for channel 3
SD4
SDA for channel 4
SC4
SCL for channel 4
SD5
SDA for channel 5
SC5
SCL for channel 5
SD6
SDA for channel 6
SC6
SCL for channel 6
SD7
SDA for channel 7
SC7
SCL for channel 7