SGLS118E December   2001  – July 2024 TPS769-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 Dissipation Ratings (Legacy Chip)
    6. 5.6 Electrical Characteristics
    7. 5.7 Typical Characteristics
    8. 5.8 Typical Characteristics: Supported ESR Range
  7. 6 Detailed Description
    1. 6.1 Overview
    2. 6.2 Functional Block Diagrams
    3. 6.3 Feature Description
      1. 6.3.1 Output Enable
      2. 6.3.2 Dropout Voltage
      3. 6.3.3 Current Limit
      4. 6.3.4 Undervoltage Lockout (UVLO)
      5. 6.3.5 Output Pulldown
      6. 6.3.6 Thermal Shutdown
    4. 6.4 Device Functional Modes
      1. 6.4.1 Normal Operation
      2. 6.4.2 Dropout Operation
      3. 6.4.3 Disabled
  8. 7 Application and Implementation
    1. 7.1 Application Information
    2. 7.2 Typical Application
      1. 7.2.1 Design Requirements
      2. 7.2.2 Detailed Design Procedure
        1. 7.2.2.1 Adjustable Device Feedback Resistors
        2. 7.2.2.2 Recommended Capacitor Types
        3. 7.2.2.3 Input and Output Capacitor Requirements
        4. 7.2.2.4 Reverse Current
        5. 7.2.2.5 Feed-Forward Capacitor (CFF)
        6. 7.2.2.6 Power Dissipation (PD)
        7. 7.2.2.7 Estimating Junction Temperature
      3. 7.2.3 Application Curves
    3. 7.3 Power Supply Recommendations
    4. 7.4 Layout
      1. 7.4.1 Layout Guidelines
      2. 7.4.2 Layout Example
  9. 8 Device and Documentation Support
    1. 8.1 Device Support
      1. 8.1.1 Development Support
        1. 8.1.1.1 Evaluation Module
        2. 8.1.1.2 Spice Models
        3. 8.1.1.3 Device Nomenclature
    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

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • DBV|5
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.2.2.6 Power Dissipation (PD)

Circuit reliability requires consideration of the device power dissipation, location of the circuit on the printed circuit board (PCB), and correct thermal plane sizing. Place few or no other heat-generating devices that cause added thermal stress in the PCB area around the regulator.

To first-order approximation, power dissipation in the regulator depends on the input-to-output voltage difference and load conditions. The following equation calculates power dissipation (PD).

Equation 7. PD = (VIN – VOUT) × IOUT
Note: Minimize power dissipation, and therefore achieve greater efficiency, by correctly selecting the system voltage rails. For the lowest power dissipation use the minimum input voltage required for correct output regulation.

For devices with a thermal pad, the primary heat conduction path for the device package is through the thermal pad to the PCB. Solder the thermal pad to a copper pad area under the device. This pad area contains an array of plated vias that conduct heat to additional copper planes for increased heat dissipation.

The maximum power dissipation determines the maximum allowable ambient temperature (TA) for the device. Power dissipation and junction temperature are most often related by the RθJA of the combined PCB, device package, and the ambient air temperature (TA). RθJA is the junction-to-ambient thermal resistance. The following equation calculates this relationship.

Equation 8. TJ = TA + (RθJA × PD)

Thermal resistance (RθJA) is highly dependent on the heat-spreading capability built into the particular PCB design. RθJA therefore varies according to the total copper area, copper weight, and location of the planes. The junction-to-ambient thermal resistance listed in the Thermal Information table is determined by the JEDEC standard PCB and copper-spreading area. RθJA is used as a relative measure of package thermal performance. RθJA is improved by 35% to 55% compared to the Thermal Information table value by optimizing the PCB board layout. See the An empirical analysis of the impact of board layout on LDO thermal performance application note for further information.