PCA9685 servo driver case (Fischertechnik or standalone)

thingiverse

A case for the PCA9685 16-Channel Servo Driver board from Adafruit and its affordable Chinese clones (see note below). The bottom part comes in two versions: a plain standalone version and one with connectors for the Fischertechnik construction toy system. The top part fits both versions and offers several options, implemented as punch-through holes: A circular hole (5mm diameter) for the large capacitor preinstalled in Chinese versions, missing by default from the Adafruit version. The Adafruit tutorial explains why and when to leave out the capacitor. In my Chinese board, I replaced the 1000 microfarad capacitor with a smaller 220 microfarad one. Two small circular holes (1.6mm diameter) for Fischertechnik female jacks as alternatives to power terminals. Solder them to the backside of the board with two short pieces of wire. Two small square holes (3.2x3.2mm) for a power LED light guide. The left position is for the current Chinese or old Adafruit version, while the right position is for the current Adafruit version. Print the light guide with transparent filament in a lying position for best results. On demand, punch out the according hole at post-print stage using a small knife, screwdriver, or drill of suitable size. Alternatively, use TinkerCAD or another 3D tool to punch them out digitally at pre-print stage. Note and warning: I learned that the original PCA9685 board is an Adafruit design after ordering a couple of boards from Chinese eBay sellers. Although the Chinese version is much cheaper, be warned that some models lack the reverse polarity protection feature from the original, even if they claim otherwise on the backside. Also, some clones have a different layout with non-centered power terminals. So I strongly recommend buying from and supporting the great folks from Adafruit, even if my pictures show the cheap Chinese version. Please consider leaving a "like" or posting your make as a token of appreciation for my work. Find my other Fischertechnik designs here: https://www.thingiverse.com/juh/designs.