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

5 Pin Configuration and Functions

RGW Package
20-Pin VQFN
Top View
TPS2372 PINOUT_72_SLUSCD1.gif

Pin Functions

PIN I/O DESCRIPTION
NAME NO.
VDD 1 I Connect to positive PoE input power rail. Bypass with 0.1 µF to VSS.
DEN 2 I/O Connect a 24.9 kΩ resistor from DEN to VDD to provide the PoE detection signature. Pull DEN to VSS to disable the pass MOSFET during powered operation.
CLSA 3 O Connect a resistor from CLSA to VSS to program the first classification current.
VSS 4, 5 — Connect to negative power rail derived from PoE source.
CLSB 6 O Connect a resistor from CLSB to VSS to program the second classification current.
REF 7 O Internal 1.5 V voltage reference. Connect a 49.9kΩ_1% resistor from REF to VSS.
AMPS_CTL 8 O Automatic MPS control. Connect a resistor with appropriate power rating (to support the MPS current) from AMPS_CTL to VSS to program the MPS current amplitude. Leave AMPS_CTL open to disable the automatic MPS function.
MPS_DUTY 9 I MPS duty cycle select input, referenced to VSS, internally driven by a precision current source with voltage limited to less than ~5.5V. A resistor connected to VSS determines if the MPS duty cycle selected is either 5.4% (open), 8.1% (~60.4 kΩ) or 12.5% (short).
AUTCLS 10 I Autoclass enable input. Internally pulled-up to 5.5 V internal rail during classification only, pulled down in other circumstances to minimize consumption. Pull low (to VSS) to enable the Autoclass function during classification. Leave open otherwise.
RTN 11, 12 — Drain of PoE pass MOSFET. Return line from the load to the controller.
PG 13 O Power Good output. Open-drain, active-high output referenced to RTN.
NC 14, 15 — No connect
IRSHDL_EN 16 I PSE inrush delay (~81.5 ms) enable, referenced to RTN, internally pulled-up to 5.5 V internal rail. Leave open to enable the inrush delay.
TPL 17 O PSE allocated power outputs, binary coded. Open-drain, active-low outputs referenced to RTN.
TPH 18 O
BT 19 O Indicates that a PSE applying an IEEE802.3bt (Type 3 or 4) mutual identification scheme has been identified. Open-drain, active-low output referenced to RTN.
NC 20 — No connect pin. Leave open.
Pad — — The exposed thermal pad must be connected to VSS. A large fill area is required to assist in heat dissipation.