3.2″ TFT LCD Display (ILI9481)

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In this article, I’ll be testing out the 3.2″ TFT LCD Display with the ILI9481 controller.

I’ve also decided to make my own interfacing circuit instead of buying a shield.

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At the back of the LCD are the pinouts and the SD card slot which can be used to load images.

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I will be using an Arduino Mega 2560 as the LCD needs a lot of I/O pins.

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Because the LCD runs on 3.3V logic and the Arduino runs on 5V logic, a logic level conversion circuit is needed for all of the data and SPI connections.

Below is the schematic diagram for the circuit. It uses 2 logic level conversion ICs, the SN74ALVC164245DL and SN74LVC4245ADW. There is also a SMD 3.3V voltage regulator to supply the required 3.3V for the logic level conversion ICs and also the LCD.

The SN74ALVC164245DL supports up to 16 channels while the SN74LVC4245ADW supports up to 8 channels.

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As expected, these ICs are SMDs (Surface Mount Device) so I made a PCB adapter board for them. The SN74ALVC164245DL in particular only comes in the SSOP package, and the pin pitch is really small (0.65mm). The PCB had to be good for the circuit to work.

Printed the PCB artwork on a wax paper. I’m using the toner transfer method.

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Cut the copper clad PCBs to size. Thoroughly cleaned and sanded to get rid of any impurities.

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Ironing process to transfer the PCB artwork onto the copper surface.

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The PCB artwork transferred onto the copper surface flawlessly.

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Next step is to immerse the board into a ferric chloride solution to get rid of the unwanted copper areas.

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Cleaned off the toner to reveal the shiny copper surface.

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Soldered the ICs onto the PCB boards.

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I intended to make another main PCB to connect all of these boards together but I was too lazy and decided to connect all of them up together through ribbon cables.

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Very messy but it works. I’m using the TFT library by Henning Karlsen.

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Here’s the LCD running the demo sequence.

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With this done I can use this LCD for my future projects.

Thanks for reading.

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