JAJSFT7A July   2018  – October 2021 TPS3431

PRODUCTION DATA  

  1. 特長
  2. アプリケーション
  3. 概要
  4. Revision History
  5. Pin Configuration and Functions
  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 Electrical Characteristics
    6. 6.6 Timing Requirements
    7. 6.7 Timing Diagrams
    8. 6.8 Typical Characteristics
  7. Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Enable Input (EN) and Enable Output (ENOUT)
      2. 7.3.2 Watchdog Mode
        1. 7.3.2.1 CWD
        2. 7.3.2.2 Watchdog Input WDI
        3. 7.3.2.3 Watchdog Output WDO
        4. 7.3.2.4 SET1
    4. 7.4 Device Functional Modes
      1. 7.4.1 VDD is Below VPOR ( VDD < VPOR)
      2. 7.4.2 Above Power-On-Reset, But Less Than VDD(min) (VPOR ≤ VDD < VDD(min))
      3. 7.4.3 Normal Operation (VDD ≥ VDD(min))
  8. Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 CWD Functionality
        1. 8.1.1.1 Factory-Programmed Timing Options
        2. 8.1.1.2 CWD Adjustable Capacitor Watchdog Timeout
    2. 8.2 Typical Application
      1. 8.2.1 Design 1 Requirements
      2. 8.2.2 Detailed Design 1 Procedure
        1. 8.2.2.1 Calculating WDO Pullup Resistor Design 1
        2. 8.2.2.2 Setting the Watchdog Design 1
      3. 8.2.3 Application Curves Design 1
    3. 8.3 Programmable Application
      1. 8.3.1 Design 2 Requirements
      2. 8.3.2 Detailed Design 2 Procedure
        1. 8.3.2.1 Calculating WDO Pullup Resistor Design 2
        2. 8.3.2.2 Setting the Watchdog Design 2
        3. 8.3.2.3 Watchdog Disabled During Initialization Period Design 2
        4. 8.3.2.4 Programmable Disable Feature Design 2
      3. 8.3.3 Application Curves Design 2
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Device Support
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 サポート・リソース
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Factory-Programmed Timing Options

If using the factory-programmed timing options (listed in Table 8-1), the CWD pin must either be unconnected or pulled up to VDD through a 10-kΩ pull-up resistor. Using these options enables high-precision, 15% accurate watchdog timing.

Table 8-1 Factory Programmed Watchdog Timing
INPUTSTANDARD WATCHDOG TIMEOUT WDT (tWD)UNIT
CWDSET1MINTYPMAX
NC0Watchdog disabled
NC1136016001840ms
10 kΩ to VDD0Watchdog disabled
10 kΩ to VDD1170200230ms