Arduino Uno Rev3

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Arduino Uno


Arduino Ethernet Shield


A microcontroller development board and software that allows you to make interactive objects.

The Arduino is an open sourced microcontroller and free programming software that allows you to make interactive objects

The Arduino Uno is a microcontroller board based on the ATmega328 (datasheet). It has 14 digital input/output pins (of which 6 can be used as PWM outputs), 6 analog inputs, a 16 MHz ceramic resonator, a USB connection, a power jack, an ICSP header, and a reset button. It contains everything needed to support the microcontroller; simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. The Uno differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega16U2 (Atmega8U2 up to version R2) programmed as a USB-to-serial converter. Revision 2 of the Uno board has a resistor pulling the 8U2 HWB line to ground, making it easier to put into DFU mode.

Revision 3 of the board has the following new features:

  • 1.0 pinout: added SDA and SCL pins that are near to the AREF pin and two other new pins placed near to the RESET pin, the IOREF that allow the shields to adapt to the voltage provided from the board.
  • Stronger RESET circuit.
  • Atmega 16U2 replace the 8U2.


  • Microcontroller: ATmega328
  • Operating Voltage: 5V
  • Input Voltage (recommended): 7-12V
  • Input Voltage (limits): 6-20V
  • Digital I/O Pins: 14 (of which 6 provide PWM output)
  • Analog Input Pins: 6
  • DC Current per I/O Pin: 40 mA
  • DC Current for 3.3V Pin: 50 mA
  • Flash Memory: 32 KB (ATmega328) of which 0.5 KB used by bootloader
  • SRAM: 2 KB (ATmega328)
  • EEPROM: 1 KB (ATmega328)
  • Clock Speed: 16 MHz

The Arduino Ethernet Shield w/PoE allows your Arduino to connect to the internet while powering your Arduino

Using the Wiznet W5100 ethernet chip, the Arduino Ethernet Shield allows an Arduino board to connect to the internet. The Wiznet chip provides a network (IP) stack capable of both TCP and UDP. The Arduino Ethernet Shield supports up to four simultaneous socket connections. Use the Ethernet library to write sketches which connect to the internet via a standard RJ45 Ethernet jack using the shield.

The Power over Ethernet (PoE) module is designed to extract power from an ethernet cable. The ethernet shield connects to an Arduino board using wire-wrap headers which extend through the shield, allowing for other compatible shields to be stacked on top.

New Available Features:

  • Micro SD card connector with active voltage translators
  • Power over Ethernet Ready
  • On board reset controller
  • Now compatible with the Arduino MEGA board
  • Supplied with PoE module

Product Specifications

  • Standard RJ45 ethernet jack
  • Operating voltage: 5V
  • Ethernet controllera: W5100 w/ internal 16k buffer
  • Connection speed: 10/100Mb
  • Connection wtih Arduino on SPI port
  • PoE module
  • IEEE802.3af compliant
  • Low output ripple and noise (100mVpp)
  • Input voltage range 36V-57V
  • Overload and short-circuit protection
  • 9V Output
  • High effeciency DC/DC converter: typ 75% @ 50% load
  • 1500V isolation (input to output)

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In 2005, Massimo Banzi and David Cuartielles initiated a project to make a device for controlling interactive design projects. It is the Arduino.

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