SLLA579 January   2022 ISOUSB211

 

  1.   Trademarks
  2. 1PCB Trace Insertion Loss and Inter-Symbol Interference
  3. 2Transmitter Pre-Emphasis and Receiver Equalizer
  4. 3Selecting an Optimal Pre-emphasis for Your System
  5. 4Eye-Diagrams for 6 inch to 4 feet Traces with all Nine Pre-Emphasis Settings for USB 2.0 Near-end Eye-mask
  6. 5Eye-Diagrams for 6 inch to 4 feet Traces and 5m Cable with all Nine Pre-emphasis Settings for USB 2.0 Far-end Eye-mask
  7. 6Using Receiver Equalizer and Transmitter Pre-emphasis for Channel Loss Compensation Simultaneously
  8. 7Summary

7 Summary

The ISOUSB211DP consists of nine transmitter pre-emphasis settings and nine equalizer settings to compensate for different trace and cable losses to enhance the system signal integrity. An USB 2.0 system with a need for isolation that struggles with ISI can benefit from using ISOUSB211DP equalizer and pre-emphasis to improve the EH and EW to meet the USB 2.0 near-end eye-mask and far-end eye-mask requirements. We have seen that the ISOUSB211 transmitter pre-emphasis and receiver equalizer manage to compensate FR4 differential trace up to 4 feet length, or less than 2dB differential loss respectively. For a system that has higher loss, you can distribute the loss on both transmitter and receiver sides and rely on the transmitter pre-emphasis and receiver equalizer to compensate for the higher loss.