SLLA535 December   2022 TLIN1431-Q1

 

  1. 1Introduction
    1.     Trademarks
  2. 2TLIN1431x-Q1 Hardware Component Functional Safety Capability
  3. 3Development Process for Management of Systematic Faults
    1. 3.1 TI New-Product Development Process
    2. 3.2 TI Functional Safety Development Process
  4. 4TLIN1431x-Q1 Component Overview
    1. 4.1 Targeted Applications
    2. 4.2 Hardware Component Functional Safety Concept
    3. 4.3 Functional Safety Constraints and Assumptions
  5. 5Description of Hardware Component Parts
    1. 5.1 LIN Transceiver
    2. 5.2 Digital Core
    3. 5.3 Power Control IP
    4. 5.4 Digital Input/Output Pins and High-side Switch
  6. 6TLIN1431x-Q1 Management of Random Faults
    1. 6.1 Fault Reporting
    2. 6.2 Functional Safety Mechanism Categories
    3. 6.3 Description of Functional Safety Mechanisms
      1. 6.3.1 LIN Bus and Communication
        1. 6.3.1.1 SM-1: LIN TXD Pin Dominant State Timeout
        2. 6.3.1.2 SM-2: LIN Bus Stuck Dominant System Fault: False Wake Up Lockout
        3. 6.3.1.3 SM-3: LIN Bus Short Circuit Limiter
        4. 6.3.1.4 SM-20: LIN Internal pull-up to VSUP
        5. 6.3.1.5 SM-22: LIN Protocol
      2. 6.3.2 Voltage Rail Monitoring
        1. 6.3.2.1 SM-4: VCC and Transceiver Thermal Shutdown
        2. 6.3.2.2 SM-5: VCC Under-voltage
        3. 6.3.2.3 SM-6: VCC Over-voltage
        4. 6.3.2.4 SM-7: VCC Short to Ground
        5. 6.3.2.5 SM-8: VSUP Under-voltage
      3. 6.3.3 Processor Communication
        1. 6.3.3.1 SM-9 and SM-10: Watchdog
          1. 6.3.3.1.1 SM-9: Standby Mode Long Window Timeout Watchdog
          2. 6.3.3.1.2 SM-10: Normal Mode Watchdog
        2. 6.3.3.2 SM-11: SPI CRC
        3. 6.3.3.3 SM-12: SPI Communication Error; SPIERR
        4. 6.3.3.4 SM-13: Scratchpad Write/Read Register
        5. 6.3.3.5 SM-14: Sleep Wake Error Timer; tINACT_FS
      4. 6.3.4 Digital Input/Output Pins and High-side Switch
        1. 6.3.4.1 SM-15: CLK internal pull-up to VINT
        2. 6.3.4.2 SM-16: SDI internal pull-up to VINT
        3. 6.3.4.3 SM-17: nCS Internal pull-up to VINT
        4. 6.3.4.4 SM-18: DIV_ON Internal pull-down to GND
        5. 6.3.4.5 SM-19: TXD Internal pull-up to VINT
        6. 6.3.4.6 SM-21: nRST Internal pull-up to VINT
        7. 6.3.4.7 SM-23: HSS Over Current Detect
        8. 6.3.4.8 SM-24: HSS Open Load Detect
          1.        A Summary of Recommended Functional Safety Mechanism Usage
            1.         B Distributed Developments
              1.          B.1 How the Functional Safety Lifecycle Applies to TI Functional Safety Products
              2.          B.2 Activities Performed by Texas Instruments
              3.          B.3 Information Provided
                1.           C Revision History

6.3.1.2 SM-2: LIN Bus Stuck Dominant System Fault: False Wake Up Lockout

The device contains logic to detect bus stuck dominant system faults and prevents the device from waking up falsely during the system fault. Upon entering sleep mode, the device detects the state of the LIN bus. If the bus is dominant, the wake-up logic is locked out until a valid recessive on the bus “clears” the bus stuck dominant, preventing excessive current use.

Figure 6-1 and Figure 6-2 show the behavior of this protection.

Figure 6-1 No Bus Fault: Entering Sleep Mode with Bus Recessive Condition and Wake Up
Figure 6-2 Bus Fault: Entering Sleep Mode with Bus Stuck Dominant Fault, Clearing, and Wake Up