SNVSCF5B June   2023  – March 2025 TPS35

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Device Comparison
  6. 5 Pin Configuration and Functions
  7. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Thermal Information
    6. 6.6  Electrical Characteristics
    7. 6.7  Timing Requirements
    8. 6.8  Switching Characteristics
    9. 6.9  Timing Diagrams
    10. 6.10 Typical Characteristics
  8. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Voltage Supervisor
      2. 7.3.2 Timeout Watchdog Timer
        1. 7.3.2.1 tWD Timer
        2. 7.3.2.2 Watchdog Enable Disable Operation
        3. 7.3.2.3 tSD Watchdog Start Up Delay
        4. 7.3.2.4 SET Pin Behavior
      3. 7.3.3 Manual RESET
      4. 7.3.4 RESET and WDO Output
    4. 7.4 Device Functional Modes
  9. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Output Assert Delay
        1. 8.1.1.1 Factory-Programmed Output Assert Delay Timing
        2. 8.1.1.2 Adjustable Capacitor Timing
      2. 8.1.2 Watchdog Timer Functionality
        1. 8.1.2.1 Factory-Programmed Timing Options
        2. 8.1.2.2 Adjustable Capacitor Timing
    2. 8.2 Typical Applications
      1. 8.2.1 Design 1: Monitoring a Microcontroller Supply Voltage and Watchdog Timer
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Setting the Voltage Threshold
          2. 8.2.1.2.2 Meeting the Watchdog Timeout Period
          3. 8.2.1.2.3 Setting the Reset Delay
          4. 8.2.1.2.4 Setting the Startup Delay and Output Topology
          5. 8.2.1.2.5 Calculating the RESET Pullup Resistor
    3. 8.3 Power Supply Recommendations
    4. 8.4 Layout
      1. 8.4.1 Layout Guidelines
      2. 8.4.2 Layout Example
  10. 9 Device and Documentation Support
    1. 9.1 Receiving Notification of Documentation Updates
    2. 9.2 Support Resources
    3. 9.3 Trademarks
    4. 9.4 Electrostatic Discharge Caution
    5. 9.5 Glossary
  11. 10Revision History
  12. 11Mechanical, Packaging, and Orderable Information

8.1.2.2 Adjustable Capacitor Timing

Adjustable tWD timing is achievable by connecting a capacitor to the CWD pin. If this method is used, please consult Equation 4 for calculating typical tWD values using the nominal capacitor value. Capacitor tolerances cause the actual device timing to vary such that the minimum of tWD can decrease and the maximum of tWD can increase by the capacitor tolerance. For the most accurate timing, use ceramic capacitors with COG dielectric material.