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

6.3.4 Digital Input/Output Pins and High-side Switch

There are internal pull-ups or pull-downs on critical terminals to place the device into known states if the terminal floats. Several of these are only active when the TLIN1431x-Q1 is in SPI control.

Table 6-9 Internal Pull-up or Pull-down table
Safety Mechanism PinPull-up or Pull-downTypical ValueComment
SM-15CLKPull-up240 kΩKeeps CLK pin from floating
SM-16SDIPull-up240 kΩKeeps SDI pin from floating
SM-17nCSPull-up240 kΩKeeps nCS from floating and enabling SPI when not intended
SM-18DIV_ONPull-down370 kΩKeeps DIV_ON pin from floating and turning on the VBAT monitor when not intended
SM-19TXDPull-up350 kΩKeeps TXD pin from floating dominant which could cause LIN but to be forced dominant
SM-20LINPull-up45 kΩKeeps LIN bus from being forced dominant which would cause RXD pin to be forced dominant
SM-21nRSTPull-up45 kΩKeeps nRST from floating and as active low pin indicates when VCC is in under-voltage, watchdog error or device is in reset mode.