SLVSCP3D January   2015  – November 2025 TPS7B4253-Q1

PRODUCTION DATA  

  1.   1
  2. 1 Features
  3. 2 Applications
  4. 3 Description
  5. 4 Pin Configuration and Functions
  6. 5 Specifications
    1. 5.1 Absolute Maximum Ratings
    2. 5.2 ESD Ratings
    3. 5.3 Recommended Operating Conditions
    4. 5.4 Thermal Information
    5. 5.5 Electrical Characteristics
    6. 5.6 Typical Characteristics
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagram
    3. 6.3 Feature Description
      1. 6.3.1 Short Circuit and Overcurrent Protection
      2. 6.3.2 Integrated Inductive Clamp Protection
      3. 6.3.3 OUT Short to Battery and Reverse Polarity Protection
      4. 6.3.4 Undervoltage Shutdown
      5. 6.3.5 Thermal Protection
      6. 6.3.6 Regulated Output (OUT)
      7. 6.3.7 Enable (EN)
      8. 6.3.8 Adjustable Output Voltage (FB and ADJ)
        1. 6.3.8.1 OUT Voltage Equal to the Reference Voltage
        2. 6.3.8.2 OUT Voltage Higher Than Reference Voltage
        3. 6.3.8.3 Output Voltage Lower Than Reference Voltage
    4. 6.4 Device Functional Modes
      1. 6.4.1 Operation With VIN < 4V
      2. 6.4.2 Operation With EN Control
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Applications
      1. 7.2.1 Application With Output Voltage Equal to the Reference Voltage
        1. 7.2.1.1 Design Requirements
        2. 7.2.1.2 Detailed Design Procedure
          1. 7.2.1.2.1 Input Capacitor
          2. 7.2.1.2.2 Output Capacitor
        3. 7.2.1.3 Application Curve
      2. 7.2.2 High-Side Switch Configuration
      3. 7.2.3 High Accuracy LDO
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
        1. 7.4.1.1 Power Dissipation and Thermal Considerations
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Device Nomenclature
      2. 8.1.2 Development Support
    2. 8.2 Documentation Support
      1. 8.2.1 Related Documentation
    3. 8.3 Receiving Notification of Documentation Updates
    4. 8.4 Support Resources
    5. 8.5 Trademarks
    6. 8.6 Electrostatic Discharge Caution
    7. 8.7 Glossary
  10. 9 Revision History
  11. 10Mechanical, Packaging, and Orderable Information
    1. 10.1 Mechanical Data

7.4.1.1 Power Dissipation and Thermal Considerations

Use Equation 5 to calculate the device power dissipation.

Equation 5. TPS7B4253-Q1

where

  • PD = continuous power dissipation
  • IO = output current
  • VI = input voltage
  • VO = output voltage
  • IQ = quiescent current

As IQ « IO, the term IQ × VI in Equation 5 can be ignored.

For a device under operation at a given ambient air temperature (TA), calculate the junction temperature (TJ) with Equation 6.

Equation 6. TPS7B4253-Q1

where

  • θJA = junction-to-junction-ambient air thermal impedance

A rise in junction temperature because of power dissipation can be calculated with Equation 7.

Equation 7. TPS7B4253-Q1

For a given maximum junction temperature (TJmax), the maximum ambient air temperature (TAmax) at which the device can operate can be calculated with Equation 8.

Equation 8. TPS7B4253-Q1