SLVSC76E February   2014  – May 2018 TPS92630-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Typical Application Schematic
  5. 5 Revision History
  6. 6 Description (Continued)
  7. 7 Pin Configuration and Functions
    1.     Pin Functions
  8. 8 Specifications
    1. 8.1 Absolute Maximum Ratings
    2. 8.2 ESD Ratings
    3. 8.3 Recommended Operating Conditions
    4. 8.4 Thermal Information
    5. 8.5 Electrical Characteristics
    6. 8.6 Timing Requirements
    7. 8.7 Typical Characteristics
  9. 9 Parameter Measurement Information
  10. 10Detailed Description
    1. 10.1 Overview
    2. 10.2 Functional Block Diagram
    3. 10.3 Feature Description
      1. 10.3.1 Constant LED-Current Setting
      2. 10.3.2 PWM Control
      3. 10.3.3 FAULT Diagnostics
      4. 10.3.4 Short-Circuit Detection
      5. 10.3.5 Open-Load Detection
      6. 10.3.6 Thermal Foldback
    4. 10.4 Device Functional Modes
      1. 10.4.1 Thermal Information
      2. 10.4.2 Operation With V(VIN) < 5 V (Minimum V(VIN))
      3. 10.4.3 Operation With 5 V < V(VIN) < 9 V (Lower-Than-Normal Automotive Battery Voltage)
  11. 11Applications and Implementation
    1. 11.1 Application Information
    2. 11.2 Typical Applications
      1. 11.2.1 Stoplight and Taillight Application With PWM Generator
        1. 11.2.1.1 Design Requirements
        2. 11.2.1.2 Detailed Design Procedure
          1. 11.2.1.2.1 Step-by-Step Design Procedure
            1. 11.2.1.2.1.1 R(REF)
            2. 11.2.1.2.1.2 Duty Cycle
            3. 11.2.1.2.1.3 Input and Output Capacitors
        3. 11.2.1.3 PWM Dimming Application Curve
      2. 11.2.2 Simple Stop-Light and Taillight Application
        1. 11.2.2.1 Design Requirements
        2. 11.2.2.2 Detailed Design Procedure
          1. 11.2.2.2.1 Step-by-Step Design Procedure
            1. 11.2.2.2.1.1 R(REF)
            2. 11.2.2.2.1.2 R(Stop)
            3. 11.2.2.2.1.3 Input and Output Capacitors
      3. 11.2.3 Parallel Connection
        1. 11.2.3.1 Design Requirements
        2. 11.2.3.2 Detailed Design Procedure
          1. 11.2.3.2.1 Step-by-Step Design Procedure
            1. 11.2.3.2.1.1 R(REF)
            2. 11.2.3.2.1.2 Input and Output Capacitors
      4. 11.2.4 Alternate Parallel Connection
        1. 11.2.4.1 Design Requirements
        2. 11.2.4.2 Detailed Design Procedure
          1. 11.2.4.2.1 Step-by-Step Design Procedure
            1. 11.2.4.2.1.1 R(REF)
            2. 11.2.4.2.1.2 Input and Output Capacitors
      5. 11.2.5 High-Side PWM Dimming
        1. 11.2.5.1 Design Requirements
        2. 11.2.5.2 Detailed Design Procedure
          1. 11.2.5.2.1 Step-by-Step Design Procedure
            1. 11.2.5.2.1.1 Ratio of Resistors, R1 / R2
            2. 11.2.5.2.1.2 R1 and R2 Selection
            3. 11.2.5.2.1.3 Input and Output Capacitors
  12. 12Power Supply Recommendations
  13. 13Layout
    1. 13.1 Layout Guidelines
    2. 13.2 Layout Example
  14. 14Device and Documentation Support
    1. 14.1 Documentation Support
      1. 14.1.1 Related Documentation
    2. 14.2 Receiving Notification of Documentation Updates
    3. 14.3 Community Resources
    4. 14.4 Trademarks
    5. 14.5 Electrostatic Discharge Caution
    6. 14.6 Glossary
  15. 15Mechanical, Packaging, and Orderable Information

13.1 Layout Guidelines

In order to prevent thermal shutdown, TJ must be less than 150°C. If the input voltage is very high, the power dissipation might be large. The devices are currently available in the TSSOP-EP package, which has good thermal impedance. However, the PCB layout is also very important. Good PCB design can optimize heat transfer, which is absolutely essential for the long-term reliability of the device.

  • Maximize the copper coverage on the PCB to increase the thermal conductivity of the board, because the major heat-flow path from the package to the ambient is through the copper on the PCB. Maximum copper is extremely important when the design does not include heat sinks attached to the PCB on the other side of the package.
  • Add as many thermal vias as possible directly under the package ground pad to optimize the thermal conductivity of the board.
  • All thermal vias should be either plated shut or plugged and capped on both sides of the board to prevent solder voids. To ensure reliability and performance, the solder coverage should be at least 85 percent.