We are sorry the previous version(V1.1) Seeeduino Mega has a 3.3v power switch bug.
Seeeduino Mega v1.21 features:
- 3.3v/5v selectable, Atmega1280 run 16MHz @ 3.3v(overclock), we have not got the potential problem;
- USB/EXT power auto select;
- enlarge the drills from 32mil to 35mil;
here you can find the Eagle source file and gerbers:
Seeeduino_v1.21.zip (408 KB)