SNLA236 September   2015 DS125BR111 , DS125BR401A , DS125BR820

 

  1.   Linear Repeaters Used in SAS/SATA Applications
    1.     Trademarks
    2. 1 Introduction
    3. 2 SAS-3 Transmit Waveforms
      1. 2.1 Default Transmit Equalization Coefficients
      2. 2.2 Using Linear Equalization to Recover Tx FIR Information
      3. 2.3 Linear Equalization Effects on Jitter Due to Attenuation
    4. 3 Equalizer Placement within a SAS-3 Channel
    5. 4 System Results Using Linear Equalization
      1. 4.1 Linear Equalization Effects on Jitter Due to Attenuation
      2. 4.2 Channel Extension
    6. 5 Passing Out Of Band (OOB) Signals
    7. 6 Conclusions
    8. 7 Appendix A: Layout Considerations
  2.   Revision History

6 Conclusions

The DS125BR820 Linear Repeater can enable SAS-3 operation beyond typical system ASIC capability. The CTLE on the DS125BR820 can provide up to 10 dB of high frequency gain helping to compensate for the additional channel losses. Full linear operation allows for consistent link training, helping to establish the best possible eye at the SAS-3 receiver. This channel extension comes without any penalty of OOB signaling amplitude or timing distortion.