LaskaKit ESPlan ESP32 LAN8720A RS485 PoE v2.1

Product detailed description

LaskaKit ESPlan is an industrial development board based on the ESP32-WROOM-32E module, combining wired Ethernet (LAN8720A), an RS485 bus, and three independent power supply options – including optional PoE. The board is designed for industrial automation, IoT gateways, home automation (Home Assistant, ESPHome), and remote sensor nodes where reliable wired connectivity without Wi-Fi dependency is required.

Power Supply – Three Options

ESPlan v2.1 supports three power sources that can be freely combined (the one with the highest voltage is always active):

• USB-C: 5 V directly from a computer or charger – ideal for development and programming. With this option, devices connected to the RS485 bus are not powered.
• Screw Terminal (+12/24 V, GND): Input voltage 12–24 V. Powered via an LMR14050 step-down converter to 5 V, followed by an XC6220 LDO to 3.3 V. Suitable for power from an industrial source or DIN rail. Devices on the RS485 bus are also powered by the same voltage connected to the terminal block.
• PoE (Power over Ethernet): Power directly from the Ethernet cable using the optional SDaPo DP9900M module (sold separately – available in 12 V or 24 V variants). The PoE module output is fed into the same step-down converter as the terminal block. For ESPlan, we recommend the 24 V variant, which better matches the converter's input range and ensures higher efficiency. The module complies with the IEEE 802.3af standard (up to 12.95 W), features galvanic isolation, and works with a PoE switch or injector that complies with the IEEE 802.3af standard or is compatible. Devices on the RS485 bus are also powered by the same voltage as the PoE output voltage.

Connectivity and Interfaces

• Ethernet: LAN8720A physical layer (Fast Ethernet 10/100 Mbps), HanRun RJ45 connector with integrated transformers and status LEDs.
• RS485: WS3081 transceiver with TVS protection, screw terminal block (12/24V, GND, A, B). The BUS_TERM jumper allows the 120 Ω termination resistor to be connected directly on the board – eliminating the need for an external terminator at the end of the line.
• Wi-Fi + Bluetooth: Built-in ESP32-WROOM-32E (2.4 GHz Wi-Fi 802.11 b/g/n, Bluetooth 4.2/BLE).
• MicroSD Card: MicroSD slot via SPI (IO2/CS, IO14/SCK, IO12/MISO, IO13/MOSI, IO34/CD).
• I²C Connector: Dedicated 4-pin µSup connector (3.3 V, GND, IO32/SCL, IO33/SDA) with pull-up resistors
• SPI Connector: Dedicated 6-pin µSup connector (IO15/CS, IO14/SCK, IO12/MISO, IO13/MOSI)
• GPIO Header: All available ESP32 pins are routed to solder pads for a header – IO4, IO5, IO16–IO19, IO21–IO23, IO25–IO27, IO32–IO35, IO39 and others.

Controls and LEDs

• RESET Button – ESP32 reset.
• IO0 (BOOT) Button – enters firmware upload mode (RESET + IO0 combination).
• Status LED on IO0 – programmable user LED.

Specifications

• MCU: ESP32-WROOM-32E (Xtensa LX6 dual-core 240 MHz, Wi-Fi + BT)
• Ethernet PHY: LAN8720A-CP, Fast Ethernet 10/100 Mbps
• RS485: WS3081, half-duplex, TVS protection, optional 120 Ω termination
• Power supply
  • USB-C: 5 V
  • Terminal Block: 7–40 V DC (12 or 24 V recommended)
  • PoE: IEEE 802.3af via DP9900M module (12 or 24 V variant, sold separately)
• Internal Power Rails: 5 V (buck LMR14050, up to 5 A) → 3.3 V (LDO XC6220)
• MicroSD: SPI, connector with card detection
• I²C Connector: IO32 (SCL), IO33 (SDA), 3.3 V, GND
• SPI Connector: IO15 (CS), IO14 (SCK), IO12 (MISO), IO13 (MOSI)
• Programming: USB-C (via UART bridge), RESET + BOOT buttons
• Compatibility: Arduino IDE, ESP-IDF, ESPHome, Tasmota, MicroPython

Package contents

• 1× LaskaKit ESPlan ESP32 LAN8720A RS485 PoE v2.1

Note

• The SDaPo DP9900M PoE module is not included – it must be ordered separately. For ESPlan, we recommend the 24 V output variant (SDaPo DP9900M – 24 V) or 12 V, depending on the availability of your PoE source.
• This product is not a standalone functional unit and may require professional installation.
• Product images are for illustrative purposes only and may sometimes differ from the actual appearance of the item. However, this does not change their basic characteristics.
• 3D Printed box is not included, you can print it or buy it separately.