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RM0090
Digital-to-analog converter (DAC)
456
Figure 67. Timing diagram for conversion with trigger disabled TEN = 0
14.3.5 DAC
output
voltage
Digital inputs are converted to output voltages on a linear conversion between 0 and V
REF+
.
The analog output voltages on each DAC channel pin are determined by the following
equation:
14.3.6 DAC
trigger
selection
If the TENx control bit is set, conversion can then be triggered by an external event (timer
counter, external interrupt line). The TSELx[2:0] control bits determine which out of 8
possible events will trigger conversion as shown in
Each time a DAC interface detects a rising edge on the selected timer TRGO output, or on
the selected external interrupt line 9, the last data stored into the DAC_DHRx register are
transferred into the DAC_DORx register. The DAC_DORx register is updated three APB1
cycles after the trigger occurs.
If the software trigger is selected, the conversion starts once the SWTRIG bit is set.
SWTRIG is reset by hardware once the DAC_DORx register has been loaded with the
DAC_DHRx register contents.
APB1_CLK
0x1AC
0x1AC
t
SETTLING
DHR
DOR
Output voltage
availa
b
le on DAC_OUT pin
ai14711
b
DACoutput V
REF
DOR
4095
--------------
×
=
Table 75. External triggers
Source
Type
TSEL[2:0]
Timer 6 TRGO event
Internal signal from on-chip
timers
000
Timer 8 TRGO event
001
Timer 7 TRGO event
010
Timer 5 TRGO event
011
Timer 2 TRGO event
100
Timer 4 TRGO event
101
EXTI line9
External pin
110
SWTRIG
Software control bit
111