Erich has posted an update on his open source ARM debug/universal board project. We wrote about it previously:
After the proof of concept phase (see “Proof of Concept: Open Source ARM SWD Debug and General Purpose Board“), the first prototypes are ready
I had the first prototypes of the board we have produced internally in my hands.
A different USB connector can be populated on the backside of the board, so it can directly be plugged into a USB port. Additionally the board can be placed into a small USB thumb drive case that way (I don’t have one for a picture now, but we use them for a different project).
Project details at MCUonEclipse project page.
Couldn’t find a schematics link. Any idea what’s all the parts between the MCU and the USB connector?
The lower parts could be the circuitry to connect/disconnect the bus (mosfet + few passives), while the upper SOT23 could be the linear regulator. BTW, I’m only guessing :-)
Schematic linked here http://mcuoneclipse.com/2015/05/20/tinyk20-usb-thumb-drive-enclosure
Very useful, thanks! For the TL;DR crowd, the sot23 parts are actually both BAS40-05W dual Schottky diodes (common cathode, NXP part desig?, 200mA). The K20 uses its own LDO regulator, one of the BAS40 duals isolates the K20 from the +5V rail, the other BAS40 dual is for the VBAT inputs.