Little2wire is my take on the classic Little Wire USB stick: surface mounted parts, as small and flat as possible, with an option for 3.3V operation, and optionally a micro or mini USB connector. Still solderable by hand!

Notice: I'm no longer selling these on Tindie. If you really want one, please get in touch - I may have some spare PCBs and parts.

The idea is not new in any way - the basic schematic + VUSB library, popularised by Little Wire, has been adopted by some successful projects: DigiSpark, Adafruit Trinket, as well as some perhaps less well-known ones like picoDuino and USBasp-t.

The design of this board is directly inspired by the latter two. The differences are:

The board in between the two little2wires below is my AVR ISP level translator, based on GTL2003 chip, with 3V3 regulator and designed to be as flat as possible.


R1Resistor array68R1206
R2Resistor array1.5kR1206
D1Zener diode3.6VSOD-323
D2Zener diode3.6VSOD-323
U1male headers2x3
C2Capacitor10uF0805optional w/IC2
C3Capacitor22uF0805optional w/IC2