Selects the source of the input to the VCC filter - either the 20-pin 3.3V VCC (default), or the optional voltage regulator which derives the power from a USB-Micro connector.
SJ3
Connects the output of the VCC filter to the XMEGA VCC network. Soldered by default.
SJ4
Connects the SMA Measure header to the resistive shunt. Soldered by default.
SJ5
Connects the SMA Glitch header to the resistive shunt. Soldered by default.
SJ7
Connects the VCC of the XMEGA board to VREF on 20-pin header. Soldered by default.