SFFSAY3 January   2026 F29H850DM , F29H850TU , F29H859TU-Q1 , F29P329SM-Q1 , F29P589DM-Q1 , F29P589DU-Q1 , TMCS1123 , TMCS1123-Q1 , TPS650362-Q1 , TPS650365-Q1

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
    1. 1.1 Background
    2. 1.2 HW/SW FuSa Analysis Process
      1. 1.2.1 Item Definition
      2. 1.2.2 Functional Safety Goal
      3. 1.2.3 Functional Safety Concept
      4. 1.2.4 Technical Safety Concept
      5. 1.2.5 HW/SW Safety Requirement
      6. 1.2.6 Dependent‑failure Analysis
    3. 1.3 TI Collaterals
      1. 1.3.1 TI Components Category
      2. 1.3.2 FuSa Collaterals for Safety MCU
  5. 2FuSa Concepts of OBC System
    1. 2.1 Item Definition
      1. 2.1.1 Item Functions
      2. 2.1.2 System Boundaries
      3. 2.1.3 External Interfaces
      4. 2.1.4 Operation Modes
    2. 2.2 Functional Safety Goal
    3. 2.3 Functional Safety Concept
    4. 2.4 Technical Safety Concept
    5. 2.5 HW/SW Safety Requirement
    6. 2.6 Dependent‑Failure Analysis
  6. 3FuSa Components of OBC System
    1. 3.1 Components Overview
    2. 3.2 Microcontroller
      1. 3.2.1 CPU
      2. 3.2.2 ADC Sample
      3. 3.2.3 PWM Generation
      4. 3.2.4 CMPSS
      5. 3.2.5 Data Transmission
      6. 3.2.6 Fault Signal Monitor and Safe State Control
    3. 3.3 Power Management IC
      1. 3.3.1 MCU Monitor
      2. 3.3.2 Shutdown Sequence
      3. 3.3.3 Power Supply
    4. 3.4 System Basis Chips
      1. 3.4.1 CAN Communication
      2. 3.4.2 Supply Voltage Rail Monitoring
      3. 3.4.3 SPI/Processor Communication
      4. 3.4.4 Device Internal EEPROM
    5. 3.5 Power Supply and Supervisor
    6. 3.6 Gate Driver
    7. 3.7 Voltage Sensor
    8. 3.8 Current Sensor
    9. 3.9 Temperature Sensor
  7. 4Summary
  8. 5References

1.2.6 Dependent‑failure Analysis

Dependent‑failure analysis (DFA) is a systematic method for identifying and mitigating failures that arise due to dependencies between systems or components that are supposed to be independent, including cascaded failures (CFs) and common-cause failures. (CCFs).

  • CF is a failure in one component that triggers a failure in another component, and both failures result from the same root cause. CF is expressed as AND gates in fault tree.

  • CCF is a single root cause that disables two or more safety-related items simultaneously.

DFA is applied throughout the FuSa design. It is performed in the concept phase and will be refined through system, hardware and software development. The objectives of DFA are:

  • Confirm the required independence or freedom from interference is sufficiently achieved in the design.

  • Define safety measures for potential dependent failures.