SBAK043 April   2026 DAC39RF10-SP , DAC39RFS10-SP

 

  1.   1
  2.   2
  3.   Trademarks
  4. 1Introduction
  5. 2Single-Event Effects
  6. 3Device and Test Board Information
  7. 4Irradiation Facility and Setup
  8. 5Test Setup and Procedures
  9. 6Single-Event Latch-Up (SEL) Results
  10. 7Single-Event Functional Interrupt (SEFI) Results
    1. 7.1 Converter Performance and Digital (DUC + JESD204C Link) Hardness
    2. 7.2 Configuration Register Hardness
    3. 7.3 SPI Programming During Irradiation
  11. 8SEU Results
    1. 8.1 JESD204C Link Monitoring Results
    2. 8.2 Digital Up-Converter and NCO Upset Recovery
    3. 8.3 Estimating Upset Rates in Unprotected Data Paths
    4. 8.4 Event Rate Calculations
    5. 8.5 Summary of Radiation Hardness
  12. 9References
  13.   A Appendix: Recommendations for Hi-Rel Systems
    1.     A.1 Summary of Rad-Hard Design Features
    2.     A.2 SPI Programming
    3.     A.3 JESD204C Reliability
    4.     A.4 Equalizer Usage in Radiation Environments
    5.     A.5 NCO Reliability
    6.     A.6 NCO Frequency and Phase Correction (Strategy #1)
    7.     A.7 NCO Frequency Correction (Strategy #2)
    8.     A.8 NCO Self-Sync/Self-Coherent Mode (Strategy #3)

A.4 Equalizer Usage in Radiation Environments

Adaptive equalization is not supported in radiation environments. A particle upset can disturb the adaptive equalizer and recovery is not guaranteed. In hi-rel applications, the user should program EQ_OVR = 1 and program a fixed equalizer level using EQLEVEL.

The adaptive equalizer can be used during prototyping to determine a good level to use. Follow this procedure:

  1. Enable the receiver with adaptive equalization (EQMODE=1, then JESD_EN=1).
  2. Verify data is received successfully. Read EQLEVEL_S to get the current state of the adaptive equalizer. Multiple reads are recommended to verify the adaptation loop has settled. Record the value for future use (for example, in host system firmware).
  3. In the radiation environment, enable the receiver with fixed equalization. Program EQLEVEL to the value obtained in step 2.