Let’s face it, full-colour TFT displays are cool and adding one to your project is going to instantly endow your project with coolness. The problem for the hobbyist is that they come with flexible flat connectors known as FPC or FFC connectors. These are designed to be soldered to a PCB using a ‘hot-bar’ device that is pressed across all the terminals at once, instantly soldering them to the board. Nice if you’ve got one.

Help is at hand. There are many suppliers on ebay that will sell you a small TFT already mated to a PCB with the FPC connector broken out into a 2.54mm DIP header. If these satisfy your needs then buy them, you’ll be saving yourself a whole lot of work.

But what if the panel you want only comes ‘naked’, or perhaps you want to drive the signals directly as you’ll have to do if you want to stream video to it. If you fall into these categories then you are going to have to tackle the FPC connector yourself, and I’m going to show you how.

Hand soldering an LCD FPC/FFC (Flexible Printed Circuit/Flexible Flat Cable) connector requires careful attention to detail and precision. Here are the general steps involved in the process:

1. Prepare the workspace: Ensure you have a clean and well-lit workspace with the necessary tools and equipment. This includes a soldering iron with a fine tip, solder, flux, tweezers, and possibly a magnifying glass for better visibility.

2. Familiarize yourself with the connector: Examine the LCD FPC/FFC connector and identify its pins and orientation. Take note of any special requirements, such as the need for additional support or protective measures like Kapton tape.

3. Prepare the LCD module: If the LCD module is separate from the PCB (Printed Circuit Board), ensure it is properly positioned and secured before soldering. Use Kapton tape or other suitable methods to hold it in place if necessary.

4. Apply flux to the connector pads: Flux helps improve solder flow and removes oxidation from the pads. Apply a small amount of flux to the connector pads using a fine brush or flux pen.

5. Tin the soldering iron tip: Preheat the soldering iron and coat the tip with a thin layer of solder. This ensures better heat transfer and facilitates soldering.

6. Solder the connector: Align the FPC/FFC connector with the corresponding pads on the PCB. Hold the connector in place using tweezers and touch the soldering iron tip to the pad while simultaneously applying a small amount of solder. Ensure a good solder joint by allowing the solder to flow onto the pad and connector pin, forming a small fillet. Repeat this process for each pin, working methodically and avoiding excessive heat exposure.

7. Inspect the solder joints: Inspect each solder joint carefully to ensure they are smooth, shiny, and free from bridges or cold joints. Use a magnifying glass if needed to check for any defects or soldering issues.

8. Test and clean the assembly: After soldering, test the LCD module and FPC/FFC connector to ensure proper functionality. Remove any excess flux residue using an appropriate cleaning agent or isopropyl alcohol.

 

It's important to note that hand soldering delicate components requires practice and skill. If you are uncertain or lack experience, it's advisable to seek guidance from a professional or consider using specialized soldering equipment for better precision and control.