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W5100

W5100

WIZnet
Widely used SPI-based Ethernet controller family offering integrated TCP/IP functionality in a single chip.
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Overview

The W5100 is a hardwired TCP/IP embedded Ethernet controller that simplifies internet connectivity by offloading the entire network stack from the host microcontroller. It features an integrated 10/100 Ethernet PHY and supports up to four independent simultaneous sockets using a 16KB internal buffer.

Why Choose This Part

The hardwired TCP/IP stack eliminates the need for complex software stacks on the host MCU, reducing both memory footprint and development time. It is highly robust against network attacks like flood pings or sync attacks, and its 5V tolerant I/O makes it easily compatible with a wide range of legacy microcontrollers.

Applications

Industrial Automation
Providing reliable Ethernet connectivity for PLCs and remote I/O modules where a stable, hardwired stack is preferred over software-based solutions.
Embedded Web Servers
Implementing simple web interfaces for monitoring or configuring small 8-bit or 16-bit MCU-based systems.
Serial-to-Ethernet Gateways
Bridging legacy RS-232 or RS-485 equipment to local networks via the W5100 SPI or parallel interface.
IoT Edge Nodes
Connecting sensors and actuators to local servers or cloud platforms with minimal host processing overhead.

Key Specifications

Function Controller
Protocol Ethernet
Interface SPI
Standards 10/100 Base-T/TX PHY
Package / Case 48-LQFP
Current - Supply 132mA
Voltage - Supply 2.97V ~ 3.63V
Operating Temperature -40degC ~ 85degC
Supplier Device Package 48-LQFP (7x7)

Getting Started

Engineers typically begin evaluation using the W5100 Ethernet Shield for the Arduino ecosystem or WIZnet official evaluation boards. The device can be interfaced via a high-speed SPI (Mode 0/3) or an 8-bit parallel system bus, and WIZnet provides a comprehensive C-based driver library to manage socket initialization and data transfer.

Also Consider

W5500 WIZnet - A more modern successor offering 8 independent sockets and a higher-speed SPI interface in a smaller package.
ENC28J60 MCHPMicrochip - A lower-cost SPI Ethernet controller for applications where the host MCU has enough flash and RAM to handle a software TCP/IP stack.
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