This is IIC/I2C Serial Interface Adapter Module.

This is a RoHS compliant I2C Serial LCD Daughter board that can be connected to a standard 16×2 or 20×4 Character Display Module that supports 4-bit mode. All Character Modules sold on our site support 4-bit mode, and nearly all commercially available 16×2 and 20×4 line character modules support it too.

This board has a PCF8574 I2C chip that converts I2C serial data to parallel data for the LCD display. There are many examples on the internet for using this board with Arduino. Do a search for “Arduino LCD PCF8574“. The I2C address is 0x3F by default, but this can be changed via 3 solder jumpers provided on the board. This allows up to 3 LCD displays to be controlled via a single I2C bus (giving each one it’s own address)

Specifications and Features:

1. 5V power supply.
2. Serial I2C control of LCD display using PCF8574.
3. Backlight can be enabled or disabled via a jumper on the board.
4. Contrast control via a potentiometer.
5. Can have 8 modules on a single I2C bus (change address via solder jumpers)address, allowing.
6. Size ：41.6 x 19.2 mm.

Package Includes:

1 x IIC/I2C Serial Interface Adapter Module