M16C6NK Datasheet, PDF (237/404 Pages) Renesas Technology Corp – 16-BIT SINGLE-CHIP MICROCOMPUTER M16C FAMILY / M16C/60 SERIES

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M16C/6N Group (M16C/6NK, M16C/6NM)
17. D/A Converter
17. D/A Converter
This is an 8-bit, R-2R type D/A converter. These are two independent D/A converters.
D/A conversion is performed by writing to the DAi register (i = 0, 1). To output the result of conversion, set the
DAiE bit in the DACON register to “1” (output enabled). Before D/A conversion can be used, the corresponding
port direction bit must be set to “0” (input mode). Setting the DAiE bit to “1” removes a pull-up from the
corresponding port.
Output analog voltage (V) is determined by a set value (n : decimal) in the DAi register.
V = VREF ✕ n/ 256 (n = 0 to 255)
VREF : reference voltage
Table 17.1 lists the performance of the D/A converter. Figure 17.1 shows the block diagram of the D/A
converter. Figure 17.2 shows the D/A converter-related registers. Figure 17.3 shows the D/A converter
equivalent circuit.
Table 17.1 D/A Converter Performance
Item
D/A conversion Method
R-2R method
Resolution
8 bits
Analog Output Pin
2 channels (DA0 and DA1)
Performance
Data bus low-order
DA0 register
R-2R resistor ladder
0
DA0
1
DA0E bit
DA1 register
R-2R resistor ladder
Figure 17.1 D/A Converter Block Diagram
0
DA1
1
DA1E bit
Rev.2.00 Nov 28, 2005 page 219 of 378
REJ09B0124-0200