SLVSB99C March   2012  – July 2015 TPS2378

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  APD Auxiliary Power Detect
      2. 7.3.2  CDB Converter Disable Bar Pin Interface
      3. 7.3.3  CLS Classification
      4. 7.3.4  DEN Detection and Enable
      5. 7.3.5  Internal Pass MOSFET
      6. 7.3.6  T2P Type-2 PSE Indicator
      7. 7.3.7  VDD Supply Voltage
      8. 7.3.8  VSS
      9. 7.3.9  PowerPAD
      10. 7.3.10 Forced, Four-Pair, High Power PoE
    4. 7.4 Device Functional Modes
      1. 7.4.1  PoE Overview
      2. 7.4.2  Threshold Voltages
      3. 7.4.3  PoE Start-up Sequence
      4. 7.4.4  Detection
      5. 7.4.5  Hardware Classification
      6. 7.4.6  Inrush and Start-up
      7. 7.4.7  Maintain Power Signature
      8. 7.4.8  Start-up and Converter Operation
      9. 7.4.9  PD Hotswap Operation
      10. 7.4.10 Start-up and Power Management, CDB and T2P
      11. 7.4.11 Adapter ORing
      12. 7.4.12 Using DEN to Disable PoE
      13. 7.4.13 ORing Challenges
  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 Resistor, RCLS
        6. 8.2.2.6 APD Pin Divider Network RAPD1, RAPD2
      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 Documentation
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

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

1 Features

  • IEEE 802.3at Type-2 Hardware Classification with Status Flag
  • Adapter Priority Input
  • DC/DC Converter Enable
  • Robust 100 V, 0.5-Ω Hotswap MOSFET
  • Operating Current up to 850 mA
  • 1-A (Typical) Operating Current Limit
  • 15 kV and 8 kV System-level ESD Capability
  • PowerPAD™ HSOP Package

2 Applications

  • IEEE 802.3at-compliant Devices
  • Video and VoIP Telephones
  • Multiband Access Points
  • Security Cameras
  • Pico-base Stations
  • Forced, Four-Pair, High Power Devices (SLVA625)

3 Description

This 8-pin integrated circuit contains all of the features needed to implement an IEEE802.3at type-2 powered device (PD). The low 0.5-Ω internal switch resistance, combined with the enhanced thermal dissipation of the PowerPAD™ package, enables this controller to continuously handle up to 0.85 A. The TPS2378 features an auxiliary power detect (APD) input, providing priority for an external power adapter. It also features a 100-V pass transistor, 140-mA inrush current limiting, type-2 indication, auto-retry fault protection, and an open-drain power-good output.

Device Information(1)

PART NUMBER PACKAGE BODY SIZE (NOM)
TPS2378 HSOP (8) 4.89 mm × 3.90 mm
  1. For all available packages, see the orderable addendum at the end of the data sheet.

Typical Application Circuit

TPS2378 typ_app_lvsb99.gif