SLVS325D March   2001  – February 2018 TPS791

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic: Fixed Output
      2.      Simplified Schematic: Adjustable Output
  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 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagrams
    3. 7.3 Feature Description
      1. 7.3.1 Power Dissipation and Junction Temperature
      2. 7.3.2 Programming the TPS79101 Adjustable Regulator
      3. 7.3.3 Regulator Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Normal Operation
      2. 7.4.2 Dropout Operation
      3. 7.4.3 Disabled
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 External Capacitor Requirements
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
      3. 8.2.3 Application Curves
    3. 8.3 Do's and Don'ts
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 Board Layout Recommendation to Improve PSRR and Noise Performance
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Receiving Notification of Documentation Updates
    2. 11.2 Community 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

7.3.1 Power Dissipation and Junction Temperature

Specified regulator operation is confirmed at a junction temperature of 125°C; restrict the maximum junction temperature to 125°C under normal operating conditions. This restriction limits the power dissipation the regulator can handle in any given application. To ensure the junction temperature is within acceptable limits, calculate the maximum allowable dissipation, PD(max), and the actual dissipation, PD, which must be less than or equal to PD(max).

The maximum-power-dissipation limit is determined using the following equation:

Equation 1. TPS791 Q_pdmax_tjmx-lvs325.gif

where

  • TJmax is the maximum allowable junction temperature
  • RθJA is the thermal resistance junction-to-ambient for the package (see the Thermal Information table)
  • TA is the ambient temperature

The regulator dissipation is calculated using:

Equation 2. PD = (VIN – VOUT) × IOUT

Power dissipation resulting from quiescent current is negligible. Excessive power dissipation triggers the thermal protection circuit.