How to Use TFT LCD 2.25″ 76×284 pixel: Examples, Pinouts, and Specs

The TFT LCD 2.25″ (EastRising ER‑TFTM2.25‑1) is a thin-film transistor liquid crystal display designed for high-quality graphical and textual output. With a resolution of 76×284 pixels, this display is ideal for compact devices requiring clear and vibrant visuals. Its slim profile and efficient design make it suitable for a wide range of applications, including handheld devices, industrial equipment, and consumer electronics.

• Wearable devices and smartwatches
• Portable medical instruments
• Industrial control panels
• IoT devices with graphical interfaces
• Consumer electronics such as remote controls and calculators

The TFT LCD module has a 10-pin interface. Below is the pinout and description:

1. Power Supply: Connect the VCC pin to a regulated 3.3V power source and the GND pins to the ground.
2. SPI Communication: Use the SCL and SDA pins to interface with a microcontroller via SPI. Ensure the microcontroller operates at 3.3V logic levels or use a level shifter if operating at 5V.
3. Control Pins:
   • Connect the RES pin to a GPIO pin on the microcontroller for resetting the display.
   • Use the DC pin to toggle between data and command modes.
   • The CS pin should be connected to a GPIO pin to enable or disable the display.
4. Backlight: Connect the BLK pin to 3.3V for constant backlight or to a PWM pin for adjustable brightness.

Since the Arduino UNO operates at 5V logic levels, a level shifter is required to interface with the TFT LCD. Below is an example wiring:

Below is a sample Arduino sketch to initialize and display text on the TFT LCD using the Adafruit GFX and Adafruit ST7735 libraries (compatible with this display):

#include <Adafruit_GFX.h>    // Core graphics library
#include <Adafruit_ST7735.h> // Hardware-specific library for ST7735

// Define TFT pins
#define TFT_CS   10  // Chip Select
#define TFT_RST  8   // Reset
#define TFT_DC   9   // Data/Command

// Initialize the display
Adafruit_ST7735 tft = Adafruit_ST7735(TFT_CS, TFT_DC, TFT_RST);

void setup() {
  // Initialize serial communication for debugging
  Serial.begin(9600);
  Serial.println("TFT LCD Test");

  // Initialize the TFT display
  tft.initR(INITR_BLACKTAB); // Initialize with ST7735 settings
  tft.fillScreen(ST77XX_BLACK); // Clear the screen with black color

  // Display text
  tft.setTextColor(ST77XX_WHITE); // Set text color to white
  tft.setTextSize(1);             // Set text size
  tft.setCursor(0, 0);            // Set cursor position
  tft.println("Hello, World!");   // Print text to the display
}

void loop() {
  // Nothing to do here
}

• Voltage Levels: Ensure all input signals are at 3.3V logic levels. Use level shifters if necessary.
• Backlight Control: For adjustable brightness, connect the BLK pin to a PWM-capable pin on the microcontroller.
• Reset Pin: Always initialize the display by toggling the RES pin at startup.
• SPI Speed: Use an appropriate SPI clock speed (e.g., 4 MHz) to ensure reliable communication.

1. Display Not Turning On:

   • Verify the power supply voltage is 3.3V.
   • Check all connections, especially the VCC and GND pins.
   • Ensure the CS pin is set low to enable the display.

2. No Output or Garbled Display:

   • Confirm the SPI connections (SCL, SDA, CS, DC) are correct.
   • Check the initialization code and ensure the correct driver (e.g., ST7735) is used.
   • Verify the RES pin is toggled during initialization.

3. Backlight Not Working:

   • Ensure the BLK pin is connected to 3.3V or a PWM signal.
   • Check for loose or incorrect connections.

4. Partial or Distorted Graphics:

   • Reduce the SPI clock speed to improve signal integrity.
   • Ensure the microcontroller is not overloaded with other tasks.

Q: Can I use this display with a 5V microcontroller?
A: Yes, but you must use level shifters to convert 5V logic signals to 3.3V.

Q: What is the maximum SPI clock speed supported?
A: The display typically supports SPI clock speeds up to 10 MHz, but 4 MHz is recommended for stable operation.

Q: Can I control the backlight brightness?
A: Yes, connect the BLK pin to a PWM-capable pin on your microcontroller for adjustable brightness.

Q: Is this display compatible with Raspberry Pi?
A: Yes, it can be used with Raspberry Pi via SPI, but you may need to modify the driver configuration.

This concludes the documentation for the TFT LCD 2.25″ 76×284 Pixel (EastRising ER‑TFTM2.25‑1).