The project here is to find ways to create a simple interface display element, as an experiment in subtractive features — removing things to create less bloat, less confusion. A return to fundamentals rather than feature creep. Not that a 4×5 matrix LED display would necessarily be an end-goal. Rather, what are the limit cases for subtractive design of interface displays? What are the benefits in terms of usability and simplicity and power consumption?
I made another version of the 4×5 matrix display driver using the MAX6953, ostensibly for Slow Messenger, but also possibly for other curious things in the “post-gui” category of explorations. It’s smaller and designed to hold the LED module off of the board so that it’d be possible to have a small setting for the messenger device. I like the idea of a device that’s stalk-like, sort of like these Copic markers I’ve been fond of as of late.
The previous version was like this image, below. You can see that the LED module fits on the board itself, so that mounting the module to fit through some kind of housing would have to take into account the footprint of the entire PCB. That became a bit tricky. I would’ve rather have the LED module at the top of a form like below, but perhaps quite a bit smaller in diameter.
That larger board also had this unfortunate layout issue — entirely my doing. The fatty 47uF capacitor was on the bottom, and the part I used is this ginormous tin can that quite often would get knocked off, or partially knocked off. In the new instance, I managed to find a EIA 3528-21 sized capacitor that’s got a low rectangular profile and put it on top, with most of the other components. I replaced the big thing for the smaller one on this board, above.