RA8875 Driver Board for 40-pin TFT Touch Displays - 800 x 480 Max

If you've ever admired the large, high-resolution TFT displays like 4", 5", or 7" screens with up to 800x480 pixels, but thought that your Arduino couldn't handle such a demanding display—what with its 60Hz refresh rate and 4 MHz pixel clock—you’re not alone. You might even have considered switching to ARM processors with built-in TTL display drivers, but you’re comfortable with your existing microcontroller and shields. So, what if I told you there’s a driver chip that could make your dream of controlling a large TFT display come true without abandoning your Arduino setup?

Enter the RA8875, a powerful TFT driver chip that’s capable of driving 800x480 pixel displays and even supports resistive touchscreens—all through just 5 SPI pins! This chip is the solution for any microcontroller that wants to display on a large screen but lacks the horsepower to directly manage such a high-demand interface. With 768KB of RAM, it can buffer the entire display and even overlay images depending on screen size. The RA8875 communicates over a simple SPI interface, utilizing basic register read/write methods without complicated protocols, making it easy to integrate into your project.

The RA8875 comes with a variety of hardware-accelerated graphics, including lines, rectangles, triangles, ellipses, and round-rectangles. It even includes an English/European font set, making drawing and rendering text quick and efficient, even over SPI. Plus, the chip supports 4-wire resistive touchscreens, allowing you to save valuable pins on your Arduino. It also includes an interrupt (IRQ) pin for handling touch events.

On the breakout board, you'll find level shifting to safely interface with 3-5V logic, a 3V regulator to provide clean power to the chip and display, and a constant-current booster for driving the backlight, with the ability to provide either 25mA or 50mA at up to 24V. The 40-pin connector ensures compatibility with a variety of TFT screens, though only those tested and sold by Adafruit are recommended to avoid damaging the driver or display.

Each RA8875 breakout comes fully assembled, tested, and includes a stick of header pins. You’ll need to pair it with a 40-pin TFT screen (available in 4.3", 5.0", and 7.0" sizes). To get started, simply download the Adafruit RA8875 library from GitHub and follow the setup instructions in the tutorial. Once connected, you’ll be able to run demos displaying graphics and text, and even interact with the touchscreen. For more advanced functionality, the datasheet offers a deeper look at all the RA8875 can do.

With the RA8875, you can easily bring large, high-quality TFT displays to life on your Arduino projects—without the need for a more powerful processor.

Specifications:

• Dimensions: 40.6mm x 48.7mm x 3.8mm