Introduction

The TXS0108E is an 8-bit bidirectional voltage-level translator that automatically detects direction and translates between different logic levels without requiring a direction control signal. Perfect for interfacing 3.3V and 5V Arduino devices with various sensors and peripherals.

Key Features

Technical Specifications

Pin Configuration

Pin	Function	Description
VCCA	Power A	1.2V-3.6V supply
VCCB	Power B	1.65V-5.5V supply
GND	Ground	Common ground
A1-A8	Channel A	Low-voltage side I/O
B1-B8	Channel B	High-voltage side I/O
OE	Output Enable	Active high (connect to VCCA if unused)

Typical Wiring (3.3V ↔ 5V)

// Basic Connection:
// VCCA → 3.3V (Arduino 3.3V)
// VCCB → 5V (Arduino 5V)
// GND → Common ground
// A1 → 3.3V device signal
// B1 → 5V device signal
// OE → VCCA (always enable)

Arduino I2C Level Shifting

// I2C Connection:
// Arduino SDA (5V) → B1
// Arduino SCL (5V) → B2
// 3.3V Device SDA → A1
// 3.3V Device SCL → A2
// VCCA → 3.3V
// VCCB → 5V
// GND → GND
// OE → VCCA

#include <Wire.h>

void setup() {
  Wire.begin(); // 5V I2C
  // 3.3V device will now safely communicate
}

SPI Level Shifting Example

// SPI Connection:
// Arduino MOSI (5V) → B3
// Arduino MISO (5V) → B4
// Arduino SCK (5V) → B5
// Arduino SS (5V) → B6
// 3.3V Device MOSI → A3
// 3.3V Device MISO → A4
// 3.3V Device SCK → A5
// 3.3V Device SS → A6

#include <SPI.h>

void setup() {
  SPI.begin(); // 5V SPI
  // 3.3V SPI device now safely connected
}

Application Notes

// Digital Read Example:
int val = digitalRead(A1); // Reads 3.3V signal safely

Troubleshooting