
RM0008
Digital-to-analog converter (DAC)
Doc ID 13902 Rev 12
249/1096
Figure 45.
DAC conversion (SW trigger enabled) with LFSR wave generation
Note:
DAC trigger must be enabled for noise generation, by setting the TENx bit in the DAC_CR
register.
12.3.9 Triangle-wave
generation
It is possible to add a small-amplitude triangular waveform on a DC or slowly varying signal.
DAC triangle-wave generation is selected by setting WAVEx[1:0] to “10”. The amplitude is
configured through the MAMPx[3:0] bits in the DAC_CR register. An internal triangle counter
is incremented three APB1 clock cycles after each trigger event. The value of this counter is
then added to the DAC_DHRx register without overflow and the sum is stored into the
DAC_DORx register. The triangle counter is incremented while it is less than the maximum
amplitude defined by the MAMPx[3:0] bits. Once the configured amplitude is reached, the
counter is decremented down to 0, then incremented again and so on.
It is possible to reset triangle wave generation by resetting WAVEx[1:0] bits.
Figure 46.
DAC triangle wave generation
APB1_CLK
0x00
0xAAA
DHR
DOR
ai14714
0xD55
SWTRIG
-!-0X;=MAXAMPLITUDE
$!#?$(2XBASEVALUE
$!#?$(2XBASEVALUE
)NCREMENTATION
AIC
$ECREMENTATION