Ethernet Shield W5100 R3 Support PoE For Arduino UNO/ Mega 2560/ Nano

Regular price $15.59

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The Ethernet Shield for connects your to the internet in mere minutes. Just plug this module onto your board, connect it to your network with an RJ45 cable(not included) and follow a few simple instructions to start controlling your world through the internet. As always with , every element of the platform – hardware, software and documentation – is freely available and open-source. This means you can learn exactly how it's made and use its design as the starting point for your own circuits. Hundreds of thousands of boards are already fueling people’s creativity all over the world, everyday.
The Ethernet Shield for allows an board to connect to the internet. It is based on the Wiznet W5100 ethernet chip. The Wiznet W5100 provides a network (IP) stack capable of both TCP and UDP. It supports up to four simultaneous socket connections. Use the Ethernet library to write sketches which connect to the internet using the shield. The ethernet shield connects to an board using long wire-wrap headers which extend through the shield. This keeps the pin layout intact and allows another shield to be stacked on top.


  • Requires an board (not included)
  • Operating voltage 5V(supplied from the board)
  • Ethernet controller: W5100 with internal 16K buffer
  • Connection speed: 10 / 100Mb
  • Connection with on SPI port


The most recent revision of the board exposes the 1.0 pinout on rev 3 of the UNO board.
The Ethernet Shield has a standard RJ-45 connection, with an integrated line transformer and Power over Ethernet enabled.
There is an onboard micro-SD card slot, which can be used to store files for serving over the network. It is compatible with the Uno and Mega (using the Ethernet library). The onboard microSD card reader is accessible through the SD Library. When working with this library, SS is on Pin 4. The original revision of the shield contained a full-size SD card slot; this is not supported.
The shield also includes a reset controller, to ensure that the W5100 Ethernet module is properly reset on power-up. Previous revisions of the shield were not compatible with the Mega and need to be manually reset after power-up.
The current shield has a power over Ethernet (PoE) designed to extract power from a conventional twisted pair category 5 Ethernet cable:

IEEE802.3af compliant
Low output ripple and noise (100mVpp)
Input voltage range 36V to 57V
Overload and short-circuit protection
9V output
High efficiency DC / DC converter: typ 75% @ 50% load
1500V isolation (input to output)

The Ethernet Shield R3 for contains a number of informational LEDs:
PWR: indicates that the board and shield are powered
LINK: indicates the presence of a network link and flashes when the shield transmits or receives data
FULLD: indicates that the network connection is full duplex
100M: indicates the presence of a 100 Mb / s network connection (as opposed to 10 Mb / s)
RX: flashes when the shield receives data
TX: flashes when the shield sends data
COLL: flashes when network collisions are detected

The solder jumper marked "INT" can be connected to allow the board to receive interrupt-driven notification of events from the W5100, but this is not supported by the Ethernet library. The jumper connects the INT pin of the W5100 to digital pin 2 of the .

Shipping List

  • Compatible Ethernet Shield R3 x1