SLVSDU9A February 2017  – March 2017


  1. Features
  2. Applications
  3. Description
  4. Revision History
  5. Pin Configuration and Functions
  6. Specifications
    1. 6.1Absolute Maximum Ratings
    2. 6.2ESD Ratings
    3. 6.3Recommended Operating Conditions
    4. 6.4Thermal Information
    5. 6.5Electrical Characteristics
    6. 6.6Switching Characteristics
    7. 6.7Typical Characteristics
  7. Detailed Description
    1. 7.1Overview
    2. 7.2Functional Block Diagram
    3. 7.3Feature Description
      1. 7.3.1Device Enable (EN)
      2. 7.3.2Adjustable Power-Good Threshold (PG, PGADJ)
      3. 7.3.3Adjustable Power-Good Delay Timer (DELAY)
      4. 7.3.4Undervoltage Shutdown
      5. 7.3.5Current Limit
      6. 7.3.6Thermal Shutdown
      7. 7.3.7Integrated Watchdog
        1. Watchdog (WTS, ROSC, FSEL and WRS)
        2. Watchdog (WTS, ROSC and FSEL)
        3. Service Signal and Watchdog Fault Outputs (WD and WDO)
        4. Status Detection (ROSC)
        5. Enable (PG and WD_EN)
        6. Initialization
        7. Watchdog Operation (WTS = Low)
        8. Watchdog Operation (WTS = High)
    4. 7.4Device Functional Modes
      1. 7.4.1Operation With Input Voltage Lower Than 4 V
      2. 7.4.2Operation With Input Voltage Higher Than 4 V
  8. Application and Implementation
    1. 8.1Application Information
    2. 8.2Typical Application
      1. 8.2.1Design Requirements
      2. 8.2.2Detailed Design Procedure
        1. Capacitor
        2. Capacitor
        3. Threshold
        4. Delay Period
        5. Setup
      3. 8.2.3Application Curves
  9. Power Supply Recommendations
  10. 10Layout
    1. 10.1Layout Guidelines
    2. 10.2Layout Example
  11. 11Device and Documentation Support
    1. 11.1Documentation Support
      1. 11.1.1Related Documentation
    2. 11.2Related Links
    3. 11.3Receiving Notification of Documentation Updates
    4. 11.4Community Resources
    5. 11.5Trademarks
    6. 11.6Electrostatic Discharge Caution
    7. 11.7Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Orderable Information


  • Qualified for Automotive Applications
  • AEC-Q100 Qualified With the Following Results:
    • Device Temperature Grade 1: –40°C to 125°C Ambient Operating Temperature Range
    • Device HBM ESD Classification Level 2
    • Device CDM ESD Classification Level C4B
  • Maximum Output Current: 300 mA
  • 4-V to 40-V Wide VIN Input-Voltage Range With Up to 45-V Transients
  • Fixed 3.3-V and 5-V Outputs
  • Maximum Dropout Voltage: 400 mV at 300 mA
  • Stable With Output Capacitor in Wide Range of Capacitance (4.7 µF to 500 µF) and ESR (0.001 Ω to 20 Ω)
  • Low Quiescent Current (I(Q))
    • < 4 µA When EN Is Low (Shutdown Mode)
    • 19 µA Typical at Light Loads With WD_EN High (Watchdog Disabled)
  • Configurable for Window Watchdog or Standard Watchdog
  • Open-to-Closed Window Ratio Configurable as 1:1 or 8:1
  • Fully Adjustable Watchdog Period (From 10 ms to 500 ms)
  • 9% Accurate Watchdog Period
  • Dedicated WD_EN Pin to Control Watchdog ON-OFF
  • Fully Adjustable Power-Good Threshold and Power-Good Delay Period
  • Low Input-Voltage Tracking to UVLO
  • Integrated Fault Protection
    • Overload Current-Limit Protection
    • Thermal Shutdown
  • 16-Pin HTSSOP Package


  • Automotive MCU Power Supply
  • Body Control Modules (BCM)
  • Body Comfort Modules
  • EV and HEV Battery Management Systems (BMS)
  • Electronic Gear Shifter
  • Transmission Control Unit (TCU)
  • Electrical Power Steering (EPS)


In automotive microcontroller or microprocessor power-supply applications, the watchdog is used to monitor the microcontroller working status to prevent software runaway. It is necessary for the watchdog to be independent of the microcontroller in a reliable system.

The TPS7B63xx-Q1 device is a family of 300-mA watchdog LDOs designed for an operating voltage up to 40 V, with typical quiescent current of only 19 µA at light load. The devices integrate a programmable function for selecting a window watchdog or standard watchdog, with an external resistor to set the watchdog time within 9% accuracy.

The PG pin on the TPS7B63xx-Q1 devices indicate when the output voltage is stable and in regulation. The power-good delay period and power-good threshold can be adjusted by selecting external components. The devices also feature integrated short-circuit and overcurrent protection. The combination of such features makes these devices particularly flexible and suitable to supply microcontroller in automotive applications.

Device Information(1)

TPS7B6333-Q1Fixed 3.3 VHTSSOP (16)
TPS7B6350-Q1Fixed 5 V
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Schematic

TPS7B6333-Q1 TPS7B6350-Q1 Pg1_app_sch_SLVSDU9.gif

Revision History

Changes from * Revision (February 2017) to A Revision

  • Changed Typical Application SchematicGo
  • Changed Dropout Voltage vs Output Current graphGo
  • Changed Load Regulation graphGo
  • Changed TPS7B63xx-Q1 Typical Application SchematicGo