描述 Description

The TPS23882B is an 8-channel power sourcing equipment (PSE) controller engineered to insert power onto Ethernet cables in accordance with the IEEE 802.3bt standard. The PSE controller can detect powered devices (PDs) that have a valid signature, complete mutual identification, and apply power.

The TPS23882B improves on the TPS2388 with reduced current sense resistors, SRAM programmability, programmable power limiting, capacitance measurement, and compatibility with TI?sFirmPSEsystem firmware (see Device Comparison Table).

Programmable SRAM enables in-field firmware upgradability over I2C to ensure IEEE compliance and interoperability with the latest PoE enabled devices. Dedicated per port ADCs provide continuous port current monitoring and the ability to perform parallel classification measurements for faster port turn on times. A 1.25-A port current limit and adjustable power limiting allows for the support of non-standard applications above 60-W sourced. The 200-mΩ current sense resistor and external FET architecture allow designs to balance size, efficiency, thermal and solution cost requirements.?

Port remapping and pin-to-pin compatibility with the TPS2388, TPS23880, and TPS23881 devices eases migration from previous generation PSE designs and enables interchangeable 2-layer PCB designs to accommodate different system PoE power configurations.

特性 Features

? IEEE 802.3bt PSE solution for PoE 2 Type-3 2-Pair power over ethernet applications
? Compatible with TI’s FirmPSE system firmware
? SRAM Programmable memory
? Programmable power limiting accuracy ±4%
? 200-mΩ Current sense resistor
? User selectable 15-W or 30-W autonomous mode with no MCU required
? Selectable 2-pair port power allocations
? 4 W, 7 W, 15.4 W, or 30 W

? Dedicated 14-bit integrating current ADC per port
? Noise immune MPS for DC disconnect
? 2% Current sensing accuracy

? 1- or 3-bit fast port shutdown input
? Auto-class discovery and power measurement
? Never Fooled 4-point detection
? Inrush and operational foldback protection
? 425-mA and 1.25-A selectable current limits
? Port re-mapping
? 8-bit or 16-bit I2C communication
? Flexible processor controlled operating modes
? Auto, semi auto and manual / diagnostic

? Per port voltage monitoring and telemetry
? –40°C to +125°C temperature operation