VREF Header

SAMC21N Xplained Pro has a 6-pin header labeled VREF on the board. This header can be used to select / apply a voltage reference to the ADC, DAC, and SDADC. Jumpers can be used to tie SADC VREF and ADC/DAC VREF to the kit target voltage from pin 1-3 and 2-4, or external voltages can be applied across pin 3-5 and 4-6.

Table 1. VREF Header
VREF header pin Pin / Net Function
1 VCC_AREF_P3V3_P5V0 Filtered kit target voltage
2 VCC_AREF_P3V3_P5V0 Filtered kit target voltage
3 PA04 SDADC voltage reference
4 PA03 ADC / DAC voltage reference
5 GND Ground
6 GND Ground