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Olimex ESP32-POE2 IoT Development Board User Manual

User manual for the Olimex ESP32-POE2, an ESP32-WROVER-E based IoT board featuring 25W PoE+ support (IEEE 802.3at), Ethernet, LiPo charging, and selectable power outputs.

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Overview

The ESP32-POE2 is an IoT development board from Olimex based on the ESP32-WROVER-E-N4R8 module, providing WiFi, Bluetooth, and Ethernet connectivity. It features advanced Power-over-Ethernet capabilities using the Texas Instruments TPS2378 controller, supporting the IEEE 802.3at (PoE+) standard with up to 25.5W power negotiation. The board offers selectable DC power outputs of 24V or 12V (up to 0.75A/1.5A), in addition to 5V and 3.3V rails for external sensors and peripherals. Hardware includes a 100Mb Ethernet interface with a Microchip LAN8720 PHY, a USB-C port for programming, a MicroSD card slot in 1-bit mode, and an integrated LiPo battery charger with monitoring. Note that this board lacks galvanic isolation on the Ethernet power supply, requiring caution when connecting external power sources or USB during PoE operation.

Use Cases

  • Industrial IoT gateways and controllers
  • PoE-powered remote sensors
  • Building automation and smart home systems
  • Environmental monitoring with wired Ethernet requirements
  • High-power IoT applications requiring 12V or 24V DC outputs

Topics

ESP32-POE2
Olimex
ESP32-WROVER-E-N4R8
TPS2378
IEEE 802.3at
PoE+
LAN8720
IoT Development Board
LiPo Battery Charger
Power-over-Ethernet
UEXT Connector

Referenced Parts

TPS2375PW

Texas Instruments

TPS2375PW (Si3402) would NOT work with 24V DC.

ESP32-WROVER-E-N4R8

Espressif Systems

ESP32-WROVER-E-N4R8 – WiFi and bluetooth module with 4MB flash, 8MB PSRAM

LAN8720

Microchip

This behavior happens when the PHY controller (LAN8720) gets powered before the ESP32 module can generate the PHY clock.

TPS2378

Texas Instruments

The PoE in ESP32-POE2 is handled by TPS2378 chip that is IEEE 802.3af-compliant, including pre- standard (legacy) PoE support.

Si3402-B

Silicon Labs

For more info refer to TPS2375PW's (Si3402-B's) datasheet.

25.50W

Maxim

minimum up to 25.50W maximum. Notice that network equipment usually reserves the maximum