LCD Ribbon Repair

taking your repair game to the next level is taking on the very fragile lcd flexible ribbons that appear to be magically bonded to the glass of the lcd take the horizontal line issue on game boy originals that everyone presumed were unfixable i showed it was possible to repair and keeping the original ribbon here however, the results were not ideal it relies on the ribbon itself being in good condition and just the contacts being weak instead, what we really want is the ability to completely replace these ribbons there are two key issues what is the ribbon, how is it made, as it is clearly different from standard flex ribbons how do we re bond it to the lcd glass standard ribbon materials luckily, i have worked with pcb production factories now on and off for 15 years and have great relationships with them, allowing me to ask them manufacturing questions since i am seeing less game boy screens working on the market, and more requests for similar lcd type repairs where the lcd is bonded to the glass, i wanted to figure this out standard flexible ribbons look like this and are made of polyamide backing (the plastic part) and copper traces sometimes coated in nickel or gold (the conductive part) there are two kinds, ffc (flat flexible cable) and fpc (flexible printed circuit) the only real difference between the two is that the first kind is always just a straight ribbon, with one to one mapping of pins the second kind shown below can be produced in any shape, style, have components on and more, traces can run anywhere, it can be multi layered and doesn't always have connectors at the end think of an fpc as basically just a pcb produced on flexible polyamide, which are often used to connect up to ffc/fpc connectors on pcbs an fpc can also just be another product all together for example, our cleanamp is an fpc even though it is a speaker amplifier product and doesn't connect to an ffc/fpc connector lcd ribbon material the question you will not find (and i could not) anywhere online is what material are lcd ribbons made of? the answer is the plastic backing, instead of being polyamide high temperature plastic, is a lower temperature polycarbonate as well as the backing changing, the traces are not made of copper but instead made of pure carbon mixed with other materials to help keep the carbon bonded together and to the base material this is why when you try and solder or repair these ribbons in the conventional way, your soldering iron will just burn a hole clean through the base material as i found some poor dude on the internet did here now we know how to produce these ribbons, we are one step closer to the repair we can ask a pcb factory to produce a flexible polycarbonate ribbon with carbon traces suitable for lcd bonding you can even ask them to add silkscreen over the top of the ribbon in all the areas not being connected or bonded bonding ribbon to glass we have a nice newly produced flexible polycarbonate ribbon, and the final step is to remove the old ribbon and re attach this new ribbon to the lcd glass to remove the old ribbon is easy, simply peel it away from the lcd glass it will pull away todo photo the next step is crucial, and it involves cleaning up any residue and carbon left on the glass so it is perfectly clean use ipa and a bamboo cloth for this ideally todo photo with the lcd glass cleaned and prepared, the last step is to re attach the new ribbon to the lcd glass this is done via heat to melt the carbon onto the lcd glass you can use a normal chisel soldering iron set to a low temperature of around 200c (polycarbonate melts at 300c), but it is not recommended instead, you want to purchase a dedicated soldering iron with a rubber ended t tip, specific for melting the ribbon back to lcd glass these can be found on aliexpress super cheap, if you search for lcd ribbon soldering iron when using the correct rubber ended tip, set your iron temperature to 350c this is because the silicon rubber lowers the temperature from the tip to the contact point, so it needs to be higher now align your new ribbon perfectly with the contacts on the lcd they can be hard to see but if you hold it up to the light you can see the changes in refraction showing where the contacts are then using the iron tip press down firmly for 5 10 seconds to bond the ribbon to the glass game boy horizontal line repair with all the new knowledge we have, it should now be possible to draw up and reproduce the horizontal ribbon of the game boy lcd, remove the old one, and re join a brand new ribbon to the lcd glass and green pcb when i get time, i will be sure to share the results here