How to Use SparkFun Voltage-Level Translator Breakout - TXB0104: Examples, Pinouts, and Specs

The SparkFun Voltage-Level Translator Breakout - TXB0104 is a versatile and essential component for interfacing digital circuits operating at different voltage levels. This breakout board utilizes the TXB0104 chip from Texas Instruments, which is a 4-bit non-inverting level shifter. It allows for bidirectional voltage translation between high-voltage (HV) and low-voltage (LV) logic levels, ranging from 1.2V to 3.6V, making it ideal for applications such as connecting a 3.3V microcontroller to 5V sensors or vice versa.

• Interfacing microcontrollers with peripherals of different voltage levels
• Data communication between devices operating at different logic levels
• Prototyping with mixed-voltage systems, such as combining 3.3V and 5V devices

• Voltage Range (LV side): 1.2V to 3.6V
• Voltage Range (HV side): 1.65V to 5.5V
• Maximum Data Rates:
  • 24 Mbps (Push-Pull)
  • 2 Mbps (Open-Drain)
• Channels: 4 bidirectional
• Operating Temperature Range: -40°C to 85°C

1. Power Connections:

   • Connect V_CCA to the lower voltage supply.
   • Connect V_CC to the higher voltage supply.
   • Connect GND to the common ground of both voltage sources.

2. Signal Connections:

   • Connect the LV logic signals to A1-A4.
   • Connect the HV logic signals to B1-B4.

3. Output Enable:

   • Connect OE to the higher voltage supply (V_CC) to enable the device.
   • To disable the device, connect OE to GND.

• Ensure that the voltage on the LV side does not exceed the voltage on the HV side.
• Avoid applying signals to the I/O pins when the device is not powered, as this can damage the chip.
• The OE pin must be high for the device to operate. If not used, connect it directly to V_CC.
• Decoupling capacitors (typically 0.1 µF) should be placed close to the V_CC and V_CCA pins to filter out noise.

• Signal Integrity Problems: Ensure that the data rate does not exceed the maximum specified for the device.
• Device Not Working: Check that the OE pin is high and that the power supply voltages are within the specified range.

• If the device is not functioning, first verify all power connections and signal connections.
• Check that the OE pin is properly connected to enable the device.
• Use an oscilloscope to verify that the voltage levels and signals are within the expected ranges.

Q: Can I use the TXB0104 for I2C or SPI communication? A: The TXB0104 is suitable for SPI but not recommended for I2C, as it does not have the necessary open-drain configuration.

Q: What happens if I connect a voltage higher than 3.6V to the LV side? A: Exceeding the maximum voltage on the LV side can damage the device. Always ensure that the voltage levels are within the specified range.

Q: Is the TXB0104 breakout board compatible with an Arduino UNO? A: Yes, the TXB0104 can be used with an Arduino UNO to translate between 5V and 3.3V logic levels.

// Example code for using the TXB0104 with an Arduino UNO
// This code assumes that the OE pin is tied to VCC and always enabled.

void setup() {
  // Initialize the digital pin as an output.
  pinMode(2, OUTPUT); // Corresponds to A1 on the TXB0104
}

void loop() {
  digitalWrite(2, HIGH);   // Set the pin to high (5V)
  delay(1000);             // Wait for a second
  digitalWrite(2, LOW);    // Set the pin to low (0V)
  delay(1000);             // Wait for a second
}

// Note: The actual logic level on the B1 pin will depend on the VCC voltage
// supplied to the TXB0104. If VCC is 3.3V, the high level will be 3.3V.

Remember to adjust the pin numbers and logic levels according to your specific application and the microcontroller you are using.