I2C Interface PCF8574 for LCD Display

The I2C interface module significantly simplifies the control of the LCD displays 1602 and 2004. Without the module, the display needs 6 I/O pins from the Arduino, one line for the contrast, plus 5 V and GND, a total of 9 connections. With the module, 2 control lines, 5 V and GND are sufficient, a total of 4 connections. The I2C address depends on the marking on the chip.

Recommended alternative with integrated module: LCD1602 LCD Blue Display with I2C Module or LCD2004 Blue LCD Display with I2C Module

Recommended Accessories:

• Character LCD Display 16x2 Blue 5V 1602
• 20x4 Character Blue LCD Display 5V 2004
• Dupont Jumper Cable Set 20cm 60 Pieces.
• Logic Level Converter 2-Channel 5V / 3.3V

Features:

• Marking PCF8574T: 0x20 to 0x27, default 0x27
• Marking PCF8574AT: 0x38 to 0x3F, default 0x3F
• I2C address adjustable via solder bridges A0, A1 and A2
• Contrast adjustable via the blue potentiometer on the module
• Backlight can be deactivated by removing the jumper labelled «LED»
• Ready-made Arduino library in the Library Manager under «LiquidCrystal_I2C»

Application Examples:

• Controlling LCD displays 1602 and 2004 via the I2C bus
• Projects with few free I/O pins on the Arduino

Documentation:

• I2C LCD with Arduino and I2C Scanner Tutorial (Last Minute Engineers)
• PCF8574 / PCF8574A Datasheet (PDF)
• LiquidCrystal_I2C Library (GitHub)

Technical Data:

• Operating voltage: 5 V
• Chip: PCF8574T or PCF8574AT, see marking
• Connections: GND, VCC, SDA, SCL
• Compatible with LCD: 1602 and 2004
• Color: Black
• Dimensions: 53 × 20 mm
• Weight: 5 g

Scope of Delivery:

• 1× I2C interface for LCD display