R01UH0822EJ0100 Rev.1.00
Page 886 of 1041
Jul 31, 2019
RX13T Group
27. D/A Converter for Generating Comparator C Reference Voltage (DA)
27.3
Operation
When the DACR.DAOE0 bit is set to 1, D/A converter is enabled and the conversion result is output.
An operation example of D/A conversion is shown below.
shows the timing of this operation.
(1) Set the data for D/A conversion in the DADPR.DPSEL bit and the DADR0 register.
(2) Set the DACR.DAOE0 bit to 1 to start D/A conversion. The DA0 output settles to the voltage corresponding to the
setting value after the conversion time tDCONV has elapsed. The DA0 output voltage is held at this level until the
DADR0 register is updated or the DAOE0 bit is set to 0. The output voltage (reference) is expressed by the
following formula:
(3) When the DADR0 register is updated, the conversion starts. The DA0 output settles at the new output voltage after
the conversion time tDCONV has elapsed.
(4) When the DAOE0 bit is set to 0, D/A conversion is disabled.
Figure 27.2
Example of 8-Bit D/A Converter Operation
Value of DADR0 register
× AVCC0
256
Write to
DADR0 register
Write to
DACR register
DADR0 register
DACR.DAOE0 bit
DA0 output
High-impedance state
t
DCONV
: D/A conversion time. Refer to the electric characteristics for the value.
Conversion
result (2)
Write to
DADR0 register
Write to
DACR register
Conversion
result (1)
Conversion data (1)
Conversion data (2)
t
DCONV
t
DCONV