Mononymous maker Rasmus, also called “rallekralle11” of Ping Hobbyelektronik, has launched a successor to the fingertip-sized Epi 32U4, constructed across the Espressif ESP32-C3 — and the Epi C3, as the brand new machine known as, is simply a smidgen bigger for all the additional options it packs.
“[Epi C3 is] a completely tiny growth board based mostly on the [Espressif] ESP32-C3,” Rasmus explains of the brand new growth board. ” It has a sturdy USB [Type]-C port sunk into the board to reduce the thickness. Beside the port are 2mm [around 0.078″] slots for the machine to be screwed down. The port additionally protrudes previous the PCB edge for flush panel mounting.”
When you’re on the lookout for a compact Espressif ESP32-C3 growth board, you may wrestle to seek out smaller than the Epi C3. (📷: Ping Hobbyelektronik)
The unique Epi 32U4 was based mostly, because the identify suggests, across the Microchip ATmega32U4, a surface-mount eight-bit AVR microprocessor. The brand new Epi C3 swaps this out for an Espressif ESP32-C3, that means a transfer to a significantly extra succesful 32-bit RISC-V processor core operating at as much as 160MHz, 400kB of static RAM (SRAM), and 4MB of flash storage, plus a Bluetooth 5.0 Low Power (BLE) radio related to an ultra-compact Johanson Expertise chip antenna, which Rasmus says presents “stunning vary for its measurement.”
Elsewhere on the board are 11 general-purpose enter/output (GPIO) pins, introduced out to castellated headers on the perimeters — although the board’s not suitable with customary solderless breadboards, because it makes use of smaller 1.27mm pin spacing to maintain the footprint to a minimal. The USB knowledge traces embody TVS diodes, there is a 500mA fuse on the facility line, and ferrite beads to cut back noise — whereas the on-board linear voltage regulator can push 600mA at 3.3V.
Rasmus has launched board design and manufacturing information for the Epi C3 on GitHub beneath an unspecified open supply license; assembled items can be found to order on Tindie at $20 every. For many who’d want to make use of an exterior antenna, Rasmus has additionally designed a variant with a U.FL connector — although this was not accessible to buy on the time of writing.