In moving to this new blog (later to be a portfolio), I’ll sometimes be posting old hacks to document them – OLEDs and the flash ram update are old hacks so far. I’ve decided to differentiate these with the category “Project DocumentPastWork.”
Some years ago, I set out to make my own OLEDs. This took a lot of persistence as many materials providers, manufacturers, and researchers refused to work with me, some of them providing their own brand of discouraging words along the way. Luckily, I was able to find several companies and people researching and working in the field who were very helpful.
Anatomy of an OLED
I was able to successfully make several differently-colored devices of varying quality level. In some cases I used indium as a cathode. Here’s what the successful stack I chose looks like:
AllWinner has been manufacturing cheap multi-core ARM processors for Android devices for some time now. It appears all of that success on the low-end has given them the funds needed to produce a high-end chip – the A80 Octa, which has 4 A15 cores and 4 A7 cores (ARM big.LITTLE).
Processor roadmap here, with specs – check out their Q4 2015 deliverable!
Ever since I saw a YDPG18A mod post where flash was upgraded (unsuccessfully), I’ve been curious about upgrading NAND flash. After I started investigating I realized the upgrade mentioned wouldn’t work, so I called the guy on it and he mentioned it didn’t work, just that he hadn’t gotten around to posting about it. If he’d found the exact same model flash chip as the existing one, soldered it on, and reflashed, it would have worked. But a lot of the flash chips used in these devices are old and hard to get ahold of. Luckily, they use a standard footprint (TSOP48), and a standard pinout used for SLC and MLC NAND flash.