ZHCA962 October   2019

 

  1.    说明
  2.    资源
  3.    特性
  4.    应用
  5.    设计图像
  6. 1System Description
    1. 1.1 Key System Specifications
    2. 1.2 Description
  7. 2System Overview
    1. 2.1 Block Diagram
    2. 2.2 Design Considerations
      1. 2.2.1 Input Power
        1. 2.2.1.1 Vpwr
        2. 2.2.1.2 3.3 V
        3. 2.2.1.3 3.3 V_ISO
      2. 2.2.2 Communication Interface
        1. 2.2.2.1 PSE I2C Communication
        2. 2.2.2.2 MCU - Host Communication
      3. 2.2.3 MSP430F523x Hardware Design
    3. 2.3 Highlighted Products
      1. 2.3.1  TPS23882
      2. 2.3.2  MSP430F523x
      3. 2.3.3  ISO7741
      4. 2.3.4  ISO7731
      5. 2.3.5  CSD19538
      6. 2.3.6  LM5017
      7. 2.3.7  LM5020
      8. 2.3.8  LM5050
      9. 2.3.9  INA240
      10. 2.3.10 REF3425
      11. 2.3.11 TPS3890
  8. 3Hardware, Software, Testing Requirement and Test Result
    1. 3.1 Required Hardware and Software
      1. 3.1.1 Hardware
      2. 3.1.2 Software
    2. 3.2 Testing and Results
      1. 3.2.1 Test Setup
        1. 3.2.1.1 Hardware Setup
        2. 3.2.1.2 LED, Test Point, Jumper and Connector Settings
          1. 3.2.1.2.1 EVM LEDs
          2. 3.2.1.2.2 EVM Test Points
          3. 3.2.1.2.3 EVM Jumpers
          4. 3.2.1.2.4 EVM Input and Output Connectors
        3. 3.2.1.3 System Firmware GUI Setup
          1. 3.2.1.3.1 PSE System Firmware GUI Installation
          2. 3.2.1.3.2 PSE System Firmware GUI Operation
      2. 3.2.2 Test Results
  9. 4Design Files
    1. 4.1 Schematic
    2. 4.2 Bill of Materials
    3. 4.3 PCB Layout Recommendations
      1. 4.3.1 Layout Prints
    4. 4.4 Altium Project
    5. 4.5 Gerber Files
    6. 4.6 Assembly Drawings
  10. 5Software Files
  11. 6Related Documentation
    1. 6.1 商标

1 System Description

This reference design provides a competitive and alternative solution.

In a multiport PSE system, the system-level software is the biggest challenge. The software handles complicated situations and addresses the following challenges:

  • The power supply is usually not able to support all ports with a full load due to size and cost constraints. The system software manages the port power with priority to keep the total power consumption below the power budget.
  • There are multiple power supplies in the system. These power supplies could be in sharing mode or backup mode. The system software shuts down low-priority ports fast enough to keep the total power consumption below the remaining power budget.
  • There are some legacy PD devices that do not present the standard PoE PD signature. The system software finds a way to supply power to these devices.
  • System software limits the port power based on the PD class levels or host configuration.
  • When there are load-step changes on multiple ports, the system software acts quickly enough to keep the power consumption below the power budget.