SLLA642 July   2024 TUSB564-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2USB Type-C With DisplayPort Alt-Mode
    1. 2.1 USB Type-C Basics
    2. 2.2 Adding USB3
    3. 2.3 Adding DisplayPort Alt-mode
  6. 3USB 4-Meter System
  7. 4USB 9-Meter System
  8. 5DisplayPort 4.6-Meter System
    1. 5.1 5.4Gbps
    2. 5.2 8.1Gbps
  9. 6DisplayPort 9.2-Meter System
  10. 7Summary
  11. 8References

3 USB 4-Meter System

As a starting point for testing, two 2 meter USB-C cables are used in the signal path. One cable is placed before the TUSB564-Q1, and the second cable is placed after the TUSB564-Q1. The bench board adds additional loss with the short pre and post-channel FR4 trace. A USB-C host is connected upstream, and measurements are taken at the end of the downstream USB cable.

USB 4-Meter System Block Diagram Figure 3-1 USB 4-Meter System Block Diagram

For this test, the equalization setting used on the TUSB564-Q1 is setting #3. This adds 2.2dB of gain on the downstream facing port. Figure 3-2 shows the results of a 5G far end USB compliance test taken at the downstream end of this system.

USB 4-Meter System Test Results Figure 3-2 USB 4-Meter System Test Results

The 5G USB compliance test is able to pass with no issues in this configuration. The eye diagram shows a defined eye opening and transition area.