SLVSER5A December   2018  – May 2021 TPS73801-SEP

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 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 Adjustable Operation
      2. 7.3.2 Fixed Operation
      3. 7.3.3 Overload Recovery
      4. 7.3.4 Output Voltage Noise
      5. 7.3.5 Protection Features
    4. 7.4 Device Functional Modes
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Output Capacitance and Transient Response
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 Thermal Considerations
      1. 10.3.1 Calculating Junction Temperature
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Support Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

10.3.1 Calculating Junction Temperature

Example: Given an output voltage of 3.3 V, an input voltage range of 4 V to 6 V, an output current range of 0 mA to 500 mA, and a maximum ambient temperature of 50°C, what is the operating junction temperature?

The power dissipated by the device is equal to:

Equation 10. IOUT(MAX)(VIN(MAX) – VOUT) + IGND(VIN(MAX))

where

  • IOUT(MAX) = 500 mA
  • VIN(MAX) = 6 V
  • IGND at (IOUT = 500 mA, VIN = 6 V) = 10 mA

So,

Equation 11. P = 500 mA × (6 V – 3.3 V) + 10 mA × 6 V = 1.41 W

The thermal resistance of the DCQ package is 50.5°C/W. So the junction temperature rise above ambient is approximately equal to:

Equation 12. 1.41 W × 50.5°C/W = 71.2°C

The junction temperature rise can then be added to the maximum ambient temperature to find the operating junction temperature (TJ):

Equation 13. TJ = 50°C + 71.2°C = 121.2°C