SLLSF27D November   2018  – June 2022 TLIN1441-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Description (continued)
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 ESD Ratings, IEC Specification
    4. 7.4 Recommended Operating Conditions
    5. 7.5 Thermal Information
    6. 7.6 Power Supply Characteristics
    7. 7.7 Electrical Characteristics
    8. 7.8 AC Switching Characteristics
    9. 7.9 Typical Characteristics
  8. 8 Parameter Measurement Information
    1. 8.1 Test Circuit: Diagrams and Waveforms
  9. 9 Detailed Description
    1. 9.1 Overview
    2. 9.2 Functional Block Diagram
    3. 9.3 Feature Description
      1. 9.3.1  LIN Pin
        1. 9.3.1.1 LIN Transmitter Characteristics
        2. 9.3.1.2 LIN Receiver Characteristics
          1. 9.3.1.2.1 Termination
      2. 9.3.2  TXD (Transmit Input)
      3. 9.3.3  RXD (Receive Output)
      4. 9.3.4  WAKE (High Voltage Local Wake Up Input)
      5. 9.3.5  WDT/CLK (Pin Programmable Watchdog Delay Input/SPI Clock)
      6. 9.3.6  WDI/SDI (Watchdog Timer Input/SPI Serial Data In)
      7. 9.3.7  PIN/nCS (Pin Watchdog Select/SPI Chip Select)
      8. 9.3.8  LIMP (LIMP Home output – High Voltage Open Drain Output)
      9. 9.3.9  nWDR/SDO (Watchdog Timeout Reset Output/SPI Serial Data Out)
      10. 9.3.10 VSUP (Supply Voltage)
      11. 9.3.11 GND (Ground)
      12. 9.3.12 EN/nINT (Enable Input/Interrupt Output in SPI Mode)
      13. 9.3.13 nRST/nWDR (Reset Output/Watchdog Timeout Reset Output)
      14. 9.3.14 VCC (Supply Output)
      15. 9.3.15 Protection Features
        1. 9.3.15.1 TXD Dominant Time Out (DTO)
        2. 9.3.15.2 Bus Stuck Dominant System Fault: False Wake Up Lockout
        3. 9.3.15.3 Thermal Shutdown
        4. 9.3.15.4 Under Voltage on VSUP
        5. 9.3.15.5 Unpowered Device and LIN Bus
    4. 9.4 Device Functional Modes
      1. 9.4.1 Normal Mode
      2. 9.4.2 Sleep Mode
      3. 9.4.3 Standby Mode
      4. 9.4.4 Failsafe Mode
      5. 9.4.5 Wake-Up Events
        1. 9.4.5.1 Wake-Up Request (RXD)
        2. 9.4.5.2 Local Wake Up (LWU) via WAKE Terminal
      6. 9.4.6 Mode Transitions
      7. 9.4.7 Voltage Regulator
        1. 9.4.7.1 VCC
        2. 9.4.7.2 Output Capacitance Selection
        3. 9.4.7.3 Low-Voltage Tracking
        4. 9.4.7.4 Power Supply Recommendation
      8. 9.4.8 Watchdog
        1. 9.4.8.1 Watchdog Error Counter
        2. 9.4.8.2 Pin Control Mode
        3. 9.4.8.3 SPI Control Programming
        4. 9.4.8.4 Watchdog Timing
    5. 9.5 Programming
      1. 9.5.1 SPI Communication
        1. 9.5.1.1 Chip Select Not (nCS)
        2. 9.5.1.2 Serial Clock Input (CLK)
        3. 9.5.1.3 Serial Data Input (SDI)
        4. 9.5.1.4 Serial Data Output (SDO)
    6. 9.6 Registers
  10. 10Application and Implementation
    1. 10.1 Application Information
    2. 10.2 Typical Application
      1. 10.2.1 Design Requirements
        1. 10.2.1.1 Normal Mode Application Note
        2. 10.2.1.2 Standby Mode Application Note
        3. 10.2.1.3 TXD Dominant State Timeout Application Note
      2. 10.2.2 Detailed Design Procedures
      3. 10.2.3 Application Curves
  11. 11Power Supply Recommendations
  12. 12Layout
    1. 12.1 Layout Guidelines
    2. 12.2 Layout Example
  13. 13Device and Documentation Support
    1. 13.1 Documentation Support
      1. 13.1.1 Related Documentation
    2. 13.2 Receiving Notification of Documentation Updates
    3. 13.3 Support Resources
    4. 13.4 Trademarks
    5. 13.5 Electrostatic Discharge Caution
    6. 13.6 Glossary
  14. 14Mechanical, Packaging, and Orderable Information

9.4.8.1 Watchdog Error Counter

The TLIN1441-Q1 has a watchdog error counter. This counter is an up down counter that increments for every missed window or incorrect input watchdog trigger event. For every correct input trigger, the counter decrements but does not drop below zero. The default trigger for this counter to trigger a nWDR output trigger is for every event. On every WD error event, the nWDR pin goes low as a watchdog error output trigger. For Pin control, the value is on every event. In SPI communication mode, this counter can be changed to the fifth or ninth consecutive incorrect input trigger. The error counter can be read at register 8'14[4:1].

The error counter is set at four by default. This means that when the watchdog error count is set at five and the first input failure is treated as if the fifth event has taken place. When set at nine and no correct inputs, the fifth event is treated as the failure event. This allows the system to check the counter after the first input trigger to see if a valid input was sent. nINT is pulled low on each incorrect watchdog input while VCC and nWDR behaves according to register configuration