Ping Hobbyelektronik
Microcontroller Boards
Keyboards & Input Devices
Epi 32U4
An extremely compact, Arduino-compatible ATmega32U4 USB Type-C dev board
Ping Hobbyelektronik
Microcontroller Boards
Keyboards & Input Devices
Epi 32U4 is a tiny, Arduino-compatible, USB-Type-C dev board powered by the ATmega32U4 microcontroller. We’ve designed it to be as small as practically possible, and it provides quite a few protective features to keep it operating well in noisy environments. That includes a fuse and ESD protection as well as a ferrite bead and a low-pass filter for analog reference in case the power supply is noisy.
Epi 32U4’s diminutive size allows you to incorporate it into just about any project. You can solder it directly to a PCB or use the included headers for a less permanent mounting solution. It is also quite easy to hand wire, as it includes mounting slots that allow you to screw it down before you begin soldering.
Epi 32U4 can act as a USB device, which makes it ideal for projects like compact keyboards, and its Type-C connector helps you future-proofs your designs. It also has more available IO ports than a standard Pro Micro, so it’s appropriate even for projects where space is not at a premium. Finally, its USB D+ and D- lines are broken out, in case your design requires a separate connector.
| Epi 32U4 | Pro micro | Elite-C V4 | Qwiic Pro micro | µduino | Beetle | PICO | |
|---|---|---|---|---|---|---|---|
| Manufacturer | Ping Hobbyelektronik | Various | Keeb | Sparkfun | µduino | DFrobot | Mellbell |
| Footprint | 22.75 x 12.75 mm | 33 x 17.75 mm | 33 x 17.75 mm | 33 x 17.75 mm | 12 x 12 mm | 20 x 22 mm | 15.25 x 15.25 mm |
| USB Type-C | Yes | No | Yes | Yes | No | No | No |
| Castellated pins | Yes | No | Yes | Yes | No | Arguably | No |
| IO available | 24 | 21 | 24 | 21 | 20 | 10 | 12 |
| Voltage regulator | No | Yes | No | Yes | Yes | No | Yes |
| Protective features | Several ¹ | None | None | None | Some ² | None | None |
| Screw mounting | Yes | No | No | No | No | No | No |
| Open Source | Yes | Yes | Unclear | Yes | Somewhat | Unclear | Unclear |
| Availability | Available | Plentiful | Available | Available | Unavailable | Available | Unavailable |
| Price | $25 | $5+ | $18 | $21.50 | $23 | $9 | $17 |
¹ Varistors for ESD and surge protection, a ferrite-bead power filter, and a low-pass filter for analog voltage reference.
² A low-pass filter for analog voltage reference.
You can find source and documentation files for Epi 32u4 in our GitHub repository. The data sheet and KiCad files are available there as well.
Epi 32U4 is assembled in Sweden, where we populate German-made PCBs with high-quality components from well-known manufacturers using an open-source Lumen PnP machine. We test each unit in our laboratory.
"[T]his new dev board called the Epi 32U4 might be the smallest ATmega platform we’ve seen so far."
"This tiny board is Arduino-compatible and offers USB Type-C connectivity, making it an excellent choice for makers and hobbyists."
"The board has many features that make it an excellent choice for many projects, such as robotics, home automation, and IoT."
Produced by Ping Hobbyelektronik in Kalmar, Sweden.
Sold and shipped by Crowd Supply.
A 16-MHz Epi 32U4 board. Includes two 1x12 pin headers, two 1x12 socket headers, a 1x5 pin header, and a 1x5 socket header
Ping hobbyelektronik is a small electronics manufacturer based in Kalmar county, Sweden. It was started with the intent of designing and producing unique Arduino-compatible microcontroller boards.
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