SLVSGE9A november   2022  – april 2023 TPS36-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Device Comparison
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics
    6. 7.6 Timing Requirements
    7. 7.7 Switching Characteristics
    8. 7.8 Timing Diagrams
    9. 7.9 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagrams
    3. 8.3 Feature Description
      1. 8.3.1 Voltage Supervisor
      2. 8.3.2 Window Watchdog Timer
        1. 8.3.2.1 tWC (Close Window) Timer
        2. 8.3.2.2 tWO (Open Window) Timer
        3. 8.3.2.3 Watchdog Enable Disable Operation
        4. 8.3.2.4 tSD Watchdog Start Up Delay
        5. 8.3.2.5 SET Pin Behavior
      3. 8.3.3 Manual RESET
      4. 8.3.4 RESET and WDO Output
    4. 8.4 Device Functional Modes
  9. 9 Application and Implementation
    1. 9.1 Application Information
      1. 9.1.1 CRST Delay
        1. 9.1.1.1 Factory-Programmed Reset Delay Timing
        2. 9.1.1.2 Adjustable Capacitor Timing
      2. 9.1.2 Watchdog Window Functionality
        1. 9.1.2.1 Factory-Programmed watchdog Timing
        2. 9.1.2.2 Adjustable Capacitor Timing
    2. 9.2 Typical Applications
      1. 9.2.1 Design 1: Monitoring Microcontroller Supply and Watchdog During Operational and Sleep Modes
        1. 9.2.1.1 Design Requirements
        2. 9.2.1.2 Detailed Design Procedure
          1. 9.2.1.2.1 Setting Voltage Threshold
          2. 9.2.1.2.2 Determining Window Timings During Operation and Sleep Modes
          3. 9.2.1.2.3 Meeting the Minimum Reset Delay
          4. 9.2.1.2.4 Setting the Watchdog Window
          5. 9.2.1.2.5 Calculating the RESET Pullup Resistor
    3. 9.3 Power Supply Recommendations
    4. 9.4 Layout
      1. 9.4.1 Layout Guidelines
      2. 9.4.2 Layout Example
  10. 10Device and Documentation Support
    1. 10.1 Receiving Notification of Documentation Updates
    2. 10.2 Support Resources
    3. 10.3 Trademarks
    4. 10.4 Electrostatic Discharge Caution
    5. 10.5 Glossary
  11. 11Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

8.3.2 Window Watchdog Timer

The TPS36-Q1 offers high precision window watchdog timer monitoring. The device is available in multiple pinout options A to D which support multiple features to meet ever expanding needs of various applications. Ensure a correct pinout is selected to meet the application needs.

The window watchdog is active when the VDD voltage is higher than the VIT- + VHYS and the RESET is deasserted after the tD time. The watchdog stays active as long as VDD > VIT- and watchdog is enabled. TPS36-Q1 family offers various startup time delay options to ensure enough time is available for the host to complete boot operation. Please refer Section 8.3.2.4 section for additional details.

The window watchdog timer frame consists of two windows namely close window (tWC) followed by open window (tWO). The device monitors the WDI pin for falling edge. User is expected to provide a valid falling edge on WDI pin in the open window. Refer Section 5 to arrive at the relevant close window and open window values needed for application. The timer value is reset when a valid falling edge is detected on WDI pin in the tWO time duration. An early fault is reported if a WDI falling edge is detected in close window. A late fault is reported if WDI falling edge is not detected in both close and open window. The device asserts RESET output for pinout options A, B and C or WDO output for pinout D for time tD in event of watchdog fault. Refer Section 8.3.4 to arrive at the relevant tD value needed for application.

Figure 8-6 shows the basic operation for window watchdog timer operation. The TPS36-Q1 watchdog functionality supports multiple features. Details are available in following sub sections.

GUID-20220629-SS0I-LZHP-9RBH-HQ3PBPQ0H7FP-low.svgFigure 8-6 Window Watchdog Timer Operation