SLUSCM4B October   2017  – November 2018 TPS2372

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
    1.     Device Images
      1.      Simplified Schematic
  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 Diagram
    3. 7.3 Feature Description
      1. 7.3.1 PG Power Good (Converter Enable) Pin Interface
      2. 7.3.2 CLSA and CLSB Classification, AUTCLS
      3. 7.3.3 DEN Detection and Enable
      4. 7.3.4 Internal Pass MOSFET and Inrush Delay Enable, IRSHDL_EN
      5. 7.3.5 TPH, TPL and BT PSE Type Indicators
      6. 7.3.6 AMPS_CTL, MPS_DUTY and Automatic MPS
      7. 7.3.7 VDD Supply Voltage
      8. 7.3.8 VSS
      9. 7.3.9 Exposed Thermal PAD
    4. 7.4 Device Functional Modes
      1. 7.4.1  PoE Overview
      2. 7.4.2  Threshold Voltages
      3. 7.4.3  PoE Startup Sequence
      4. 7.4.4  Detection
      5. 7.4.5  Hardware Classification
      6. 7.4.6  Autoclass
      7. 7.4.7  Inrush and Startup
      8. 7.4.8  Maintain Power Signature
      9. 7.4.9  Startup and Converter Operation
      10. 7.4.10 PD Hotswap Operation
      11. 7.4.11 Startup and Power Management, PG and TPH, TPL, BT
      12. 7.4.12 Using DEN to Disable PoE
  8. 8 Application and Implementation
    1. 8.1 Application Information
    2. 8.2 Typical Application
      1. 8.2.1 Design Requirements
      2. 8.2.2 Detailed Design Requirements
        1. 8.2.2.1  Input Bridges and Schottky Diodes
        2. 8.2.2.2  Protection, D1
        3. 8.2.2.3  Capacitor, C1
        4. 8.2.2.4  Detection Resistor, RDEN
        5. 8.2.2.5  Classification Resistors, RCLSA and RCLSB
        6. 8.2.2.6  Opto-isolators for TPH, TPL and BT
        7. 8.2.2.7  Automatic MPS and MPS Duty Cycle, RMPS and RMPS_DUTY
        8. 8.2.2.8  Internal Voltage Reference, RREF
        9. 8.2.2.9  Autoclass
        10. 8.2.2.10 Inrush Delay
      3. 8.2.3 Application Curves
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
    3. 10.3 EMI Containment
    4. 10.4 Thermal Considerations and OTSD
    5. 10.5 ESD
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Links
      2. 11.1.2 Related Documentation
    2. 11.2 Receiving Notification of Documentation Updates
    3. 11.3 Community Resources
    4. 11.4 Trademarks
    5. 11.5 Electrostatic Discharge Caution
    6. 11.6 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Refer to the PDF data sheet for device specific package drawings

Mechanical Data (Package|Pins)
  • RGW|20
Thermal pad, mechanical data (Package|Pins)
Orderable Information

7.4.6 Autoclass

Autoclass is a classification mechanism that allows a PD to communicate its effective maximum power consumption to the PSE. This happens in such a way that the PSE will be able to set the power budget to the effective maximum PD power including the effective channel losses and additional margin. This new feature was introduced in the IEEE802.3bt standard to allow a more efficient use of the available power since only the effectively used power needs to be budgeted.

A Type 3 or Type 4 PD may optionally support Autoclass whereas a Type 3 or Type 4 PSE may make use of it to optimize its power management.

A PSE implementing Autoclass uses the first class event to inquire if the PD supports Autoclass, looking for the class current to fall to class 0 current level after a time tACS, as shown in Figure 17. If it is the case, the PSE can then proceed to Autoclass measurement immediately after power up, the PD being required to draw its highest power throughout the period bounded by the next 1.35 second to 3.65 seconds. Note that the average power is calculated using any sliding window with a width in the range of 150 to 300 ms .