原标题：TI TPS23861四端口以太网供电设备(PSE)控制方案

　　TI公司的TPS23861是容易使用的以太网IEEE802.3a供电设备 (PSE)解决方案,不需要外接元件能自动管理四个802.3at端口.可以自动检测受电设备 (PD)和分类,满足IEEE 400-ms TPON 标准,主要用在以太网交换和路由器,住宅区网关,PoE传递系统,无线回传, 监测NVR和DVR等.本文介绍了TPS23861主要特性,框图和功能框图,多种应用电路,以及评估模块TPS23861EVM-612主要特性,电路图,材料清单和PCB元件布局图.

　　The TPS23861 is an easy-to-use, flexible, IEEE802.3at PSE solution. As shipped, it automatically manages four 802.3at ports without the need for any external control.

　　The TPS23861 automatically detects Powered Devices (PDs) that have a valid signature, determines power requirements according to classification and applies power. Two-event classification is supported for type-2 PDs. The TPS23861 supports DC disconnection and the external FET architecture allows designers to balance size, efficiency and solution cost requirements.

　　The unique pin-out enables 2-layer PCB designs via logical grouping and clear upper and lower differentiation of I2C and power pins. This delivers best-in-class thermal performance, Kelvin accuracy and low-build cost.

　　In addition to automatic operation, the TPS23861 supports semi auto-mode via I2C control for precision monitoring and intelligent power management. Compliance with the 400-ms TPON specification is ensured whether in semi-automatic or automatic mode.

　　TPS23861主要特性:

　　IEEE 802.3at Quad Port PSE Controller

　　Auto Detect, Classification

　　Auto Turn-On and Disconnect

　　Efficient 255-mΩ Sense Resistor

　　Pin-Out Enables Two-Layer PCB

　　Kelvin Current Sensing

　　4-Point Detection

　　Automatic Mode – As Shipped

　　No External Terminal Setting Required

　　No Initial I2C Communication Required

　　Semi-Automatic Mode – Set by I2C Command

　　Continuous Identification and Classification

　　Meets IEEE 400-ms TPON Specification

　　Fast-Port Shutdown Input

　　Optional I2C Control and Monitoring

　　–40°C to 125°C Temperature Range

　　TSSOP28 Package 9.8 mm x 6.6 mm

　　TPS23861应用:

　　Ethernet Switches and Routers

　　Surveillance NVR and DVRs

　　Residential Gateways

　　PoE Pass-Through Systems

　　Wireless Backhaul

　　图1. TPS23861简化框图

　　图2. TPS23861功能框图

　　图3. TPS23861自动四端口工作电路图

　　图4. TPS23861带端口重置的两端口自动模式应用电路图

　　图4. TPS23861四端口自动模式应用电路图

　　图5. TPS23861八端口半自动模式工作电路图

　　评估模块TPS23861EVM-612

　　TPS23861EVM-612 Evaluation Module for Quad IEEE 802.3at PoE PSE Controller

　　This user’s guide describes the evaluation modules (EVM) for the TPS23861 (TPS23861EVM-612). The EVM contains evaluation and reference circuitry for the TPS23861. The TPS23861 is a Power-over-Ethernet (PoE) device for power sourcing equipment (PSE).

　　The TPS23861EVM-612 features the quad port, TPS23861, IEEE 802.3at PoE PSE controller. The EVM consists of a motherboard (TPS23861EVM-612) and daughter board (TPS23861EVM-613) containing two TPS23861 devices. The TPS23861EVM-612 provides a multi-port base platform interface for TPS23861EVM-613, MSP-EXP430G2 (LaunchPad™), and USB-TO-GPIO (USB Interface Adapter).

　　评估模块TPS23861EVM-612主要特性:

　　• TPS23861 PSE devices default to auto-mode operation so no operator interface over I2C is required.

　　• Four IEEE802.3at, Type 2 (30 W) ports with 1000BASE-T (gigabit Ethernet data pass through)

　　• Two non-standard, high power ports with 1000BASE-T (gigabit Ethernet data pass through)

　　• Fully certified using UNH-IOL Clause #33 PSE Conformance Test Suite

　　• Single DC power supply input

　　• On board 3.3-V regulator

　　• On board I2C interface to both TPS23861PW devices from either USB-TO-GPIO or MSP-EXP430G2.

　　• Port ON status LEDs

　　• User test points

　　评估模块TPS23861EVM-612应用:

　　• Ethernet switches and routers

　　• Surveillance VDRs

　　• High power PoE

　　• PoE pass-through systems

　　图6.评估模块TPS23861EVM-612外形图

　　评估模块TPS23861EVM-612材料清单:

　　评估模块TPS23861EVM-613材料清单