20×4 LCD Display is required if you want to add some visual output to your Arduino projects. If you have few IO lines to play with, the Parallel 20×4 LCD Display with IIC/I2C interface is a quite good solution.
Check out this instructable to learn how to use this product.
This is LCD2004 Parallel LCD Display that provides a simple and cost-effective solution for adding a 20×4 White on RGB Liquid Crystal Display into your project. The display is 20 character by 4 line display has a very clear and high contrast white text upon a green background/backlight.
This is a great green backlight LCD display. It is fantastic for Arduino based project. This LCD2004 Parallel LCD Display with Green Backlight is very easy to interface with Arduino or Other Microcontrollers.
This display overcomes the drawback of LCD2004 Parallel LCD Display in which you’ll waste about 8 Pins on your Arduino for the display to get working. Luckily in this product, an I2C adapter is directly soldered right onto the pins of the display. So all you need to connect are the I2C pins, which shows a good library and little of coding.
The I2C is a type of serial bus developed by Philips, which uses two bidirectional lines, called SDA (Serial Data Line) and SCL (Serial Clock Line). Both must be connected via pulled-up resistors. The usage voltages are standard as 5V and 3.3V.
If you already have the I2C adapter soldered onto the board like in this product, the wiring is quite easy. You should usually have only four pins to hook up. VCC and GND of course. The LCD display works with 5 Volts. So we go for the 5V Pin.