SFFS143 December   2021 TCAN1164-Q1

 

  1.   Trademarks
  2. 1Introduction
  3. 2Hardware Component Failure Modes Effects and Diagnostics Analysis (FMEDA)
    1. 2.1 Random Fault Estimation
      1. 2.1.1 Fault Rate Estimation Theory for Packaging
      2. 2.1.2 Fault Estimation Theory for Silicon Permanent Faults
      3. 2.1.3 Fault Estimation Theory for Silicon Transient Faults
      4. 2.1.4 The Classification of Failure Categories and Calculation
    2. 2.2 Using the FMEDA Spreadsheet Tool
      1. 2.2.1 Mission Profile Tailoring Tab
        1. 2.2.1.1 Confidence Level
        2. 2.2.1.2 Geographical Location
        3. 2.2.1.3 Life Cycle
        4. 2.2.1.4 Use Case Thermal Management Control (Theta-Ja) and Use Case Power
        5. 2.2.1.5 Safe vs Non-Safe (Safe Fail Fraction) for Each Component Type
        6. 2.2.1.6 Analog FIT Distribution Method
        7. 2.2.1.7 Operational Profile
      2. 2.2.2 Pin Level Tailoring Tab
      3. 2.2.3 Function and Diag Tailoring Tab
      4. 2.2.4 Diagnostic Coverage Tab
      5. 2.2.5 Customer Defined Diagnostics Tab
      6. 2.2.6 Totals - ISO26262 Tab
      7. 2.2.7 Details - ISO26262 Tab
    3. 2.3 Example Calculation of Metrics
      1. 2.3.1 Assumptions of Use for Calculation of Safety Metrics
      2. 2.3.2 Summary of ISO 26262 Safety Metrics at Device Level

2.3.2 Summary of ISO 26262 Safety Metrics at Device Level

Table 2-2 provides estimates of FIT rates and calculated safety metrics per ISO 26262-5:2018 using previously noted assumptions for the device.

Table 2-2 ISO 26262 FIT Rate Estimates and Safety Metrics
DiePackageOverall
PermanentTransientPermanentSum
Total FIT (Raw FIT)λ8.131.209.9819.31
Safety Related FITλSR8.131.209.7419.08
Probabilistic Metrics for Random Hardware Failures (in FIT)PMHF2.490.600.583.67
Single Point Fault Metric SPFM69.36%50.00%94.06%80.75%
Latent Fault MetricLFM83.77%NA94.44%90.37%