SLVS933D July   2009  – December 2020 TPS23753A

PRODUCTION DATA  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Product Information
  6. 6 Pin Configuration and Functions
  7. 7 Specifications
    1. 7.1 Absolute Maximum Ratings
    2. 7.2 ESD Ratings
    3. 7.3 Recommended Operating Conditions
    4. 7.4 Thermal Information
    5. 7.5 Electrical Characteristics: Controller Section Only
    6. 7.6 Electrical Characteristics: PoE and Control
    7. 7.7 Typical Characteristics
  8. 8 Detailed Description
    1. 8.1 Overview
    2. 8.2 Functional Block Diagram
    3. 8.3 Feature Description
      1. 8.3.1 Pin Description
        1. 8.3.1.1  APD
        2. 8.3.1.2  BLNK
        3. 8.3.1.3  CLS
        4. 8.3.1.4  CS
        5. 8.3.1.5  CTL
        6. 8.3.1.6  DEN
        7. 8.3.1.7  FRS
        8. 8.3.1.8  GATE
        9. 8.3.1.9  RTN
        10. 8.3.1.10 VB
        11. 8.3.1.11 VC
        12. 8.3.1.12 VDD
        13. 8.3.1.13 VDD1
        14. 8.3.1.14 VSS
    4. 8.4 Device Functional Modes
      1. 8.4.1  Threshold Voltages
      2. 8.4.2  PoE Start-Up Sequence
      3. 8.4.3  Detection
      4. 8.4.4  Hardware Classification
      5. 8.4.5  Maintain Power Signature (MPS)
      6. 8.4.6  TPS23753A Operation
        1. 8.4.6.1 Start-Up and Converter Operation
        2. 8.4.6.2 PD Self-Protection
        3. 8.4.6.3 Converter Controller Features
      7. 8.4.7  Special Switching MOSFET Considerations
      8. 8.4.8  Thermal Considerations
      9. 8.4.9  FRS and Synchronization
      10. 8.4.10 Blanking – RBLNK
      11. 8.4.11 Current Slope Compensation
      12. 8.4.12 Adapter ORing
      13. 8.4.13 Protection
      14. 8.4.14 Frequency Dithering for Conducted Emissions Control
  9. 9 Application and Implementation
    1. 9.1 Application Information
    2. 9.2 Typical Application
      1. 9.2.1 Design Requirements
      2. 9.2.2 Detailed Design Procedure
      3. 9.2.3 Application Curves
  10. 10Power Supply Recommendations
  11. 11Layout
    1. 11.1 Layout Guidelines
    2. 11.2 Layout Example
  12. 12Device and Documentation Support
    1. 12.1 Documentation Support
      1. 12.1.1 Related Documentation
    2. 12.2 Support Resources
    3. 12.3 Electrostatic Discharge Caution
    4. 12.4 Glossary
  13. 13Mechanical, Packaging, and Orderable Information

Package Options

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

8.4.13 Protection

A TVS across the rectified PoE voltage per Figure 9-1 must be used. For general indoor applications, TI recommends an SMAJ58A or a part with equal to or better performance. If an adapter is connected from VDD1 to RTN, as in ORing option 2 above, voltage transients caused by the input cable inductance ringing with the internal PD capacitance can occur. Adequate capacitive filtering or a TVS must limit this voltage to be within the Absolute Maximum Ratings. Configurations that use DVDD as in Figure 8-10 may require additional protection against ESD transients that would turn DVDD off and force all the voltage to appear across the internal hotswap MOSFET. CVDD and DRTN per Figure 8-10 provide this additional protection.

GUID-C3B3BD97-4204-448F-A78E-00C984D2D2E8-low.gifFigure 8-10 Additional Protection Against ESD

Outdoor applications require more extensive protection to lightning standards.