SFFS035A December   2020  – February 2022 LM5157-Q1 , LM51571-Q1

 

  1.   Trademarks
  2. 1Overview
  3. 2Functional Safety Failure In Time (FIT) Rates
  4. 3Failure Mode Distribution (FMD)
  5. 4Pin Failure Mode Analysis (Pin FMA)
  6. 5Revision History

Functional Safety Failure In Time (FIT) Rates

This section provides Functional Safety Failure In Time (FIT) rates for LM5157-Q1 and LM51571-Q1 based on two different industry-wide used reliability standards:

  • Table 2-1 provides FIT rates based on IEC TR 62380 / ISO 26262 part 11
  • Table 2-2 provides FIT rates based on the Siemens Norm SN 29500-2
Table 2-1 Component Failure Rates per IEC TR 62380 / ISO 26262 Part 11
FIT IEC TR 62380 / ISO 26262FIT (Failures Per 109 Hours)
Total Component FIT Rate15
Die FIT Rate8
Package FIT Rate7

The failure rate and mission profile information in Table 2-1 comes from the Reliability data handbook IEC TR 62380 / ISO 26262 part 11:

  • Mission Profile: Motor Control from Table 11
  • Power dissipation: 850 mW
  • Climate type: World-wide Table 8
  • Package factor (lambda 3): Table 17b
  • Substrate Material: FR4
  • EOS FIT rate assumed: 0 FIT
Table 2-2 Component Failure Rates per Siemens Norm SN 29500-2
TableCategoryReference FIT RateReference Virtual TJ
5CMOS/BICMOS ASIC
Analog and Mixed ≤50 V supply
25 FIT55°C

The Reference FIT Rate and Reference Virtual TJ (junction temperature) in Table 2-2 come from the Siemens Norm SN 29500-2 tables 1 through 5. Failure rates under operating conditions are calculated from the reference failure rate and virtual junction temperature using conversion information in SN 29500-2 section 4.