SCEA147 September   2024 TXB0104 , TXB0302 , TXB0304

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2TXB-Type Architecture Differences
    1. 2.1 TXB0104 and TXB0304 Comparison
    2. 2.2 Recommended Device Selection
  6. 3Common Design Challenges
    1. 3.1 Distributed Load (Transmission Line Effect)
      1. 3.1.1 Cable Length Impact - Bench Findings
    2. 3.2 Impedance Matching
      1. 3.2.1 Bench Setup and Results
    3. 3.3 Lumped Load
  7. 4Case Study
  8. 5Summary
  9. 6References

1 Introduction

TI’s level translation portfolio includes Auto Bi-Directional, Direction Controlled, and Fixed Direction translators. The TXB-Type level shifters fall under the Auto Bi-Directional translators and can support push-pull driver signals capable of direction change per channel (for example, QSPI). To achieve this functionality, the TXB’s I/Os are designed with weak DC drive strength to allow outputs to override existing inputs when the signal changes direction. As a result, the recommendation is that the system designers do not use the TXB to drive signals through long traces or high loads due to the weakened output drivers. Instead, the Fixed-Direction Voltage Translators are suggested.

For a list of recommended level translation devices for common interface types please visit TI’s Voltage Translators and Level Shifters page.