Digital-to-analog converter

Digital-to-analog converter (DAC) converts a digital signal into an analog voltage. The AVR xmega DAC output voltage can range from 0 to the reference voltage. The DAC digital input resolution is 12-bit and the throughput is up to 1 million conversions per second (MSPS) per channel.

The input value can be provided as 12-bit or 8-bit, similarly to the ADC. The ATxmega128A1U controller has 2 DAC modules, each with 2 channels, for a total of 4 DAC outputs. The reference voltage can be AVcc, the internal 1.00 V, or the analog reference inputs AREFA or AREFB.

// Enable DACA and channel CH0
DACA.CTRLA = (DAC_CH0EN_bm|DAC_ENABLE_bm);
// Set DACA channel CH0 to single-channel mode
DACA.CTRLB = (DAC_CHSEL_SINGLE_gc);
// Set DACA reference voltage to AVcc
DACA.CTRLC = (DAC_REFSEL_AVCC_gc);
 
// Wait until the previous conversion is finished
while((DACA.STATUS & DAC_CH0DRE_bm) == 0);
// Set DACA CH0 output to ~2V
DACA.CH0DATA = 2000;