Datasheet

Section 18 D/A Converter
Rev. 6.00 Mar. 18, 2010 Page 710 of 982
REJ09B0054-0600
18.4 Operation
Two channels of the D/A converter can perform conversion individually.
When the DAOE bit in DACR is set to 1, D/A conversion is enabled and the conversion results are
output.
An example of D/A conversion of channel 0 is shown below. The operation timing is shown in
figure 18.2.
1. Write conversion data to DADR0.
2. When the DAOE0 bit in DACR is set to 1, D/A conversion starts. After the interval of t
DCONV
,
the conversion results are output from the analog output pin DA0. The conversion results are
output continuously until DADR0 is modified or DAOE0 bit is cleared to 0. The output value
is calculated by the following formula:
(DADR contents) / 256 × Vref
3. Conversion starts immediately after DADR0 is modified. After the interval of t
DCONV
,
conversion results are output.
4. When the DAOE bit is cleared to 0, analog output is disabled.
DADR0
write cycle
DACR
write cycle
DADR0
write cycle
DACR
write cycle
Address
φ
DADR0
DAOE0
DA0
Conversion data (1) Conversion data (2)
High impedance state
Conversion result (1)
Conversion result (2)
t
DCONV
t
DCONV
Legend:
t
DCONV
:
D/A conversion time
Figure 18.2 D/A Converter Operation Example