How to Use TXS0108E High Speed Full Duplex Shifter 8 Way 8 Channel Logic Level Conversion Module 8-Bit 8 CH: Examples, Pinouts, and Specs

The TXS0108E is an 8-channel bidirectional logic level converter designed to enable seamless communication between devices operating at different voltage levels. Manufactured by DEVMO, this module supports high-speed, full-duplex voltage translation, making it ideal for interfacing between 1.2V to 3.6V and 1.65V to 5.5V logic levels. Its compact design and robust performance make it a popular choice for applications requiring reliable voltage level shifting.

• Interfacing 3.3V microcontrollers (e.g., Arduino, ESP32) with 5V peripherals (e.g., sensors, displays).
• Communication between low-voltage ICs and high-voltage systems.
• I2C, SPI, UART, and GPIO signal level translation.
• Mixed-voltage system designs in embedded systems, IoT devices, and robotics.

The following table outlines the key technical specifications of the TXS0108E module:

The TXS0108E module has 10 pins, as described in the table below:

1. Power Supply Connections:

   • Connect the VCCA pin to the lower voltage supply (e.g., 3.3V).
   • Connect the VCCB pin to the higher voltage supply (e.g., 5V).
   • Ensure that GND is connected to the ground of both voltage domains.

2. Enable the Module:

   • Pull the OE pin HIGH to enable the module. If not used, connect it to VCCA through a pull-up resistor.

3. Connect Logic Signals:

   • Connect the low-voltage signals to the A1–A8 pins.
   • Connect the corresponding high-voltage signals to the B1–B8 pins.

4. Verify Connections:

   • Ensure that the voltage levels on VCCA and VCCB are within the specified ranges.
   • Double-check the wiring to avoid short circuits or incorrect connections.

• Pull-Up Resistors: For open-drain communication protocols like I2C, external pull-up resistors are required on both sides of the module.
• Signal Integrity: Keep the wiring between the module and connected devices as short as possible to minimize signal degradation.
• Power Sequencing: Power up VCCA before VCCB to ensure proper operation.
• Output Enable: If the module is not in use, pull the OE pin LOW to disable all channels and reduce power consumption.

The following example demonstrates how to use the TXS0108E to interface a 3.3V sensor with a 5V Arduino UNO.

• VCCA: Connect to Arduino's 3.3V pin.
• VCCB: Connect to Arduino's 5V pin.
• GND: Connect to Arduino's GND.
• OE: Connect to Arduino's 3.3V pin (or use a pull-up resistor).
• A1: Connect to the sensor's data pin.
• B1: Connect to Arduino's digital pin (e.g., D2).

// Example code for reading data from a 3.3V sensor using TXS0108E
// connected to a 5V Arduino UNO.

const int sensorPin = 2; // Arduino pin connected to TXS0108E B1
int sensorValue = 0;     // Variable to store sensor data

void setup() {
  pinMode(sensorPin, INPUT); // Set sensor pin as input
  Serial.begin(9600);        // Initialize serial communication
}

void loop() {
  // Read the sensor value from the TXS0108E module
  sensorValue = digitalRead(sensorPin);

  // Print the sensor value to the Serial Monitor
  Serial.print("Sensor Value: ");
  Serial.println(sensorValue);

  delay(500); // Wait for 500ms before the next reading
}

1. No Signal Translation:

   • Cause: The OE pin is not enabled.
   • Solution: Ensure the OE pin is pulled HIGH (connected to VCCA).

2. Incorrect Voltage Levels:

   • Cause: Mismatched voltage supplies on VCCA and VCCB.
   • Solution: Verify that VCCA and VCCB are within the specified ranges.

3. Signal Distortion or Noise:

   • Cause: Long wires or poor connections.
   • Solution: Use shorter wires and ensure secure connections.

4. I2C Communication Fails:

   • Cause: Missing pull-up resistors.
   • Solution: Add appropriate pull-up resistors to the I2C lines on both sides.

Q1: Can the TXS0108E handle analog signals?
A1: No, the TXS0108E is designed for digital logic level translation only.

Q2: What happens if I connect VCCA and VCCB to the same voltage?
A2: The module will still function, but level shifting will not occur since both sides operate at the same voltage.

Q3: Can I use the TXS0108E for SPI communication?
A3: Yes, the TXS0108E supports high-speed SPI communication, provided the data rate is within the module's specifications.

Q4: Is the TXS0108E suitable for 1.8V to 5V translation?
A4: Yes, the module supports voltage translation between 1.2V to 3.6V (VCCA) and 1.65V to 5.5V (VCCB).