In this note, we are going to learn about 20×4 LCD Display or LCD Module and about its specifications and pin details. Welcome to Poly Notes Hub, a leading destination for polytechnic notes for diploma and degree engineering students.

Author Name: Arun Paul.

What is 20×4 LCD Display?

A 20×4 LCD Display is a liquid crystal display (LCD) module having a display area of 20 characters in width and 4 lines in height. These modules are widely used in electrical devices to show text, numbers, and symbols. They often have a simple interface that allows people to interact with the device and examine crucial data.

Specifications of 20×4 LCD Display

Here we listed the specifications of 20×4 LCD Module –

• Display Size: 20 characters per line over four lines.
• Character size: It has typically 5×8 dots per character.
• Display Type: Typically uses reflective LCD technology.
• Interface: Typically supports parallel or serial communication protocols such as UART, SPI, and I2C.
• Voltage: The operating voltage normally ranges from 3.3 to 5 volts.
• Backlight: An LED backlight may be included to improve visibility.
• Controller: Uses an integrated controller chip, such as the Hitachi HD44780 or comparable.
• Operating Temperature: Generally works between -20°C and +70°C.
• Physical measurements: Vary, but they are usually around 98mm x 60mm x 12mm.
• Compatibility: Compatible with a variety of microcontrollers and development boards, including Arduino and Raspberry Pi.

20×4 LCD Display Pinout

Below we listed the pins of 20×4 LCD module and their function –

1. VSS: Ground (GND).
2. VDD: The power supply voltage (VCC).
3. VO: Contrast adjustment (connects to a potentiometer for adjustment)
4. RS: Register Select (RS) – Switches between command and data modes
5. RW: Read/write (R/W) – Chooses between read and write modes (typically connected to ground for write-only operation).
6. E: Enable signal (EN) – Enables data read and write.
7. D0-D7: Data lines for 8-bit mode transmission (D0 is the least significant bit, whereas D7 is the most significant bit).
8. A: Backlight anode (positive terminal, usually linked to a resistor and subsequently to VCC).
9. K: backlight cathode (negative terminal, connected to ground).