2pcs IIC I2C Serial Interface Board Module LCD1602 Address Changeable Arduino 1602/2004 I2C Interface 4-Wire 1602/2004 screen Arduino IIC/I2C Interface LCD1602/2004 adapter plate without LCD screen Arduino control board IO port is only 20, plus some sensor, SD card Han, relay modules and more, IO port is not enough, The original 1602/2004 screen requires 7 IO port can drive up, we have developed this module can help you save five IO ports, we send arduino library Product parameters: 1. Dimensions: 41.5mm (length) x 19mm (W) x 15.3mm (height) 2. Weight: 5g 3. PCB Color: Black 4. Supply Voltage :2.5-6V 5. Supports the I2C protocol 6. With backlight power control, can be connected via jumper settings are backlight power. Plug the jumper to connect the backlight off, unplug the jumper to disconnect the backlight power 7. Contrast can be adjusted by turning the blue potentiometer clockwise increase, counterclockwise weakened. Potentiometer design on the front, enabling customers to freely adjust anytime 8. Modules can be cascaded to cascade up to eight. By short-circuiting A0/A1/A2 modify the device address. The default address is 0x27. Note: Please contact us if you need the Schematic and Datasheet.