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

6 Using Receiver Equalizer and Transmitter Pre-emphasis for Channel Loss Compensation Simultaneously

In the previous sections, the trace is either located upstream or downstream of the ISOUSB211 isolated repeater. Hence, we use either receiver equalizer or transmitter pre-emphasis to compensate for the trace loss. For a system that has a trace differential loss greater than 2 dB, it is recommended to distribute the loss to the upstream and the downstream of the ISOUSB211 and use the receiver equalizer and the transmitter pre-emphasis to compensate for the trace loss simultaneously. Figure 6-1 shows ISOUSB211EVM located between the FR-4 traces. In this setup, the receiver equalizer and the transmitter pre-emphasis work together to compensate for the total trace loss; the receiver equalizer compensates for the upstream trace loss, and the transmitter pre-emphasis compensates for the downstream trace loss.

Figure 6-1 Using RXEQ and RX PE for Trace Loss Compensation