An ATtiny85 on a stick. kinda like digispark but i like my design more :)
- U1: ATtiny85-20SU
- R1: 1K5 0603
- R2,R3: 68R 0603
- C1: 10uF tantalum EIA-3216
- C2: .1uF ceramic 0603
- D1, D2: 3V6 zener SOD-323
- unlike digispark, the mcu runs on 5V, the usb data lines are shiftes using zeners and a pullup, but the headers are at 5V level.
- the ISP header is AVR standard 6pin, plus I marked the VCC and GND pins (because they're missing on the PB header)
- the PB header is the whole port B in logical order (Pin1=PB0 .. Pin6=PB5)
- use something like V-USB (or even hack a digispark firmware if you're into arduinos) with PB2=D+ and PB0=D- to use usb data.
- since PB0 and PB2 are part of port B (the only port on a tiny85), those are ALSO on the PB header, for when you don't want to use usb data, or want to probe your connection etc.
Note: for best fit and durability you should use ENIG coating and 2mm PCB thickness, but that's rather expensive, so if you just want a quick prototype to toy around with, go for the defaults and glue a piece of cardboard to the back if it falls out of your USB port.
If your application requires a license, that'd be MIT (tl;dr: do whatever you want, just don't claim it's yours). Feel free to contact me at the email in the bottom solder mask with any questions (including getting the KiCad source files) or feedback.