SNVSA91F September   2015  – April 2021 LP5910

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 No-Load Stability
      2. 7.3.2 Thermal Overload Protection
      3. 7.3.3 Short-Circuit Protection
      4. 7.3.4 Output Automatic Discharge
      5. 7.3.5 Reverse Current Protection
    4. 7.4 Device Functional Modes
      1. 7.4.1 Enable (EN)
  8. 8 Applications and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Procedure
        1. 8.2.2.1 External Capacitors
        2. 8.2.2.2 Input Capacitor
        3. 8.2.2.3 Output Capacitor
        4. 8.2.2.4 Capacitor Characteristics
        5. 8.2.2.5 Remote Capacitor Operation
        6. 8.2.2.6 No-Load Stability
        7. 8.2.2.7 Enable Control
        8. 8.2.2.8 Power Dissipation
        9. 8.2.2.9 Estimating Junction Temperature
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
      1. 10.1.1 DSBGA Mounting
      2. 10.1.2 DSBGA Light Sensitivity
    2. 10.2 Layout Examples
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Support Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary

Package Options

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

8.2.2.9 Estimating Junction Temperature

The EIA/JEDEC standard recommends the use of psi (Ψ) thermal characteristics to estimate the junction temperatures of surface mount devices on a typical PCB board application. These characteristics are not true thermal resistance values, but rather package specific thermal characteristics that offer practical and relative means of estimating junction temperatures. These psi metrics are determined to be significantly independent of copper-spreading area. The key thermal characteristics (ΨJT and ΨJB) are given in Section 6.4 and are used in accordance with Equation 4 or Equation 5.

Equation 4. TJ(MAX) = TTOP + (ΨJT × PD(MAX))

where

  • PD(MAX) is explained in Equation 1.
  • TTOP is the temperature measured at the center-top of the device package.
Equation 5. TJ(MAX) = TBOARD + (ΨJB × PD(MAX))

where

  • PD(MAX) is explained in Equation 1.
  • TBOARD is the PCB surface temperature measured 1-mm from the device package and centered on the package edge.

For more information about the thermal characteristics ΨJT and ΨJB, see the Semiconductor and IC Package Thermal Metrics application report, available for download at www.ti.com.

For more information about measuring TTOP and TBOARD, see the Using New Thermal Metrics application report, available for download at www.ti.com.

For more information about the EIA/JEDEC JESD51 PCB used for validating RθJA, see the Thermal Characteristics of Linear and Logic Packages Using JEDEC PCB Designs application report, available for download at www.ti.com.