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 by DEVMO is an 8-channel bidirectional logic level converter designed to facilitate communication between devices operating at different voltage levels. It supports high-speed data transfer and is particularly useful for interfacing 3.3V and 5V systems. This module is ideal for applications involving microcontrollers, sensors, and other peripherals that require voltage level translation.

• Interfacing 3.3V microcontrollers (e.g., Arduino, ESP32, Raspberry Pi) with 5V peripherals.
• Communication between sensors and devices operating at different voltage levels.
• Bidirectional data transfer in I2C, SPI, UART, and GPIO applications.
• Voltage level shifting in mixed-voltage systems.

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

1. Power Connections:

   • Connect the low-voltage supply (e.g., 3.3V) to the VCCA pin.
   • Connect the high-voltage supply (e.g., 5V) to the VCCB pin.
   • Connect the GND pin to the ground of your circuit.

2. Enable the Module:

   • Pull the OE (Output Enable) pin HIGH to activate the module. If left LOW, the module will be disabled.

3. Connect Data Lines:

   • Connect the low-voltage device's data lines to the A1–A8 pins.
   • Connect the high-voltage device's data lines to the corresponding B1–B8 pins.
   • Ensure that each channel is connected to the correct corresponding pin (e.g., A1 ↔ B1, A2 ↔ B2).

4. Verify Voltage Levels:

   • Ensure that the voltage levels of the connected devices match the voltage ranges specified for VCCA and VCCB.

• Pull-Up Resistors: For open-drain communication protocols like I2C, external pull-up resistors may be required on both sides of the module.
• Output Enable: Always ensure the OE pin is HIGH during operation. If not used, connect it to VCCA.
• Power Supply Sequencing: Power up VCCA before VCCB to avoid potential damage to the module.
• Data Rate: For high-speed communication, ensure the connected devices support the required data rates.

Below is an example of using the TXS0108E to interface a 3.3V sensor with a 5V Arduino UNO.

• VCCA: Connect to the 3.3V pin of the Arduino.
• VCCB: Connect to the 5V pin of the Arduino.
• GND: Connect to the Arduino's GND.
• OE: Connect to the 3.3V pin of the Arduino.
• A1: Connect to the sensor's data pin.
• B1: Connect to the 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 B1 of TXS0108E
int sensorValue = 0;

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

void loop() {
  sensorValue = digitalRead(sensorPin); // Read sensor value
  Serial.println(sensorValue);          // Print the value to Serial Monitor
  delay(500);                           // Wait for 500ms
}

1. Module Not Working:

   • Ensure the OE pin is pulled HIGH. Without this, the module will remain disabled.
   • Verify that VCCA and VCCB are powered correctly and within the specified voltage ranges.

2. Data Not Transmitting:

   • Check the connections between the A and B pins. Ensure they are correctly paired (e.g., A1 ↔ B1).
   • For I2C communication, ensure pull-up resistors are present on both sides.

3. Voltage Mismatch:

   • Confirm that the connected devices operate within the voltage ranges specified for VCCA and VCCB.

4. Signal Distortion at High Speeds:

   • Ensure the wiring is short and properly shielded to minimize noise and signal degradation.

Q1: Can I use the TXS0108E for SPI communication?
Yes, the TXS0108E supports SPI communication. Ensure that the SPI clock speed does not exceed the module's maximum data rate.

Q2: What happens if I leave the OE pin floating?
If the OE pin is left floating, the module may not function correctly. Always pull it HIGH to enable the module.

Q3: Can I use the TXS0108E with 1.8V devices?
Yes, the module supports 1.8V devices as long as the VCCA voltage is set within the range of 1.2V to 3.6V.

Q4: Is the TXS0108E suitable for analog signals?
No, the TXS0108E is designed for digital signals only. It is not suitable for analog signal conversion.