SBVS285 February   2017 TPS3852-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Typical Application Circuit
      2.      Undervoltage Threshold (VITN) Accuracy vs Temperature
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
    1.     Pin 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 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 Undervoltage Fault Detection
      4. 7.3.4 Watchdog Mode
        1. 7.3.4.1 SET1
        2. 7.3.4.2 Window Watchdog Timer
        3. 7.3.4.3 Watchdog Input (WDI)
        4. 7.3.4.4 CWD
        5. 7.3.4.5 Watchdog Output (WDO)
    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 3.3-V Rail
        2. 8.2.2.2 Calculating RESET and the WDO Pullup Resistor
        3. 8.2.2.3 Setting the Window 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 Development Support
        1. 11.1.1.1 Evaluation Module
      2. 11.1.2 Device Nomenclature
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DRB|8
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.3.3 Undervoltage Fault Detection

The TPS3852-Q1 features undervoltage detection for common rails between 1.8 V and 5 V. The voltage is monitored on the input rail of the device. If VDD drops below VITN, then RESET is asserted (driven low). When VDD is above VITN + VHYST, RESET deasserts after tRST, as shown in Figure 16. The internal comparator has built-in hysteresis that provides some noise immunity and ensures stable operation. Although not required in most cases, for noisy applications, good analog design practice is to place a 1-nF to 100-nF bypass capacitor close to the VDD pin to reduce sensitivity to transient voltages on the monitored signal.

TPS3852-Q1 undervoltage_comp_bvs302.gifFigure 16. Undervoltage Detection