SBVS286A March   2017  – September 2021 TPS3851-Q1

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 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. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 RESET
      2. 7.3.2 Manual Reset MR
      3. 7.3.3 UV Fault Detection
      4. 7.3.4 Watchdog Mode
        1. 7.3.4.1 CWD
        2. 7.3.4.2 Watchdog Input WDI
        3. 7.3.4.3 Watchdog Output WDO
        4. 7.3.4.4 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. 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 Adjustable Capacitor Timing
      2. 8.1.2 Overdrive Voltage
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 Monitoring the 1.8-V Rail
        2. 8.2.2.2 Calculating the RESET and WDO Pullup Resistor
        3. 8.2.2.3 Setting the Watchdog
        4. 8.2.2.4 Watchdog Disabled During Initialization Period
      3. 8.2.3 Glitch Immunity
      4. 8.2.4 Application Curves
  9. 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
      1. 11.1.1 Device Nomenclature
    2. 11.2 Documentation Support
      1. 11.2.1 Related Documentation
    3. 11.3 Receiving Notification of Documentation Updates
    4. 11.4 Support Resources
    5. 11.5 Trademarks
    6. 11.6 Electrostatic Discharge Caution
    7. 11.7 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

8.2.1 Design Requirements

PARAMETERDESIGN REQUIREMENTDESIGN RESULT
Watchdog disable for initialization periodWatchdog must remain disabled for 5 seconds until logic enables the watchdog timer5.02 seconds (typ)
Output logic voltage1.8-V CMOS1.8-V CMOS
Monitored rail1.8 V with a 5% thresholdWorst-case VITN = 1.714 V – 4.7%
Watchdog timeout10 ms, typicaltWD(min) = 7.3 ms, tWD(TYP) = 9.1 ms, tWD(max) = 11 ms
Maximum device current consumption50 µA37 µA when RESET or WDO is asserted (1)
(1) Only includes the TPS3851G18S-Q1 current consumption.