m38039g6hsp Renesas Electronics Corporation., m38039g6hsp Datasheet - Page 60

• Manufacturer Part Number: m38039g6hsp
• Description: Single-chip 8-bit Cmos Microcomputer
• Manufacturer: Renesas Electronics Corporation.

3803 Group (Spec.H QzROM version)
Rev.1.10
REJ03B0166-0110
D/A CONVERTER
The 3803 group (Spec.H QzROM version) has two internal D/A
converters (DA
The D/A conversion is performed by setting the value in each
DA conversion register. The result of D/A conversion is output
from the DA
“1”.
When using the D/A converter, the corresponding port direction
register bit (P3
status).
The output analog voltage V is determined by the value n
(decimal notation) in the DA conversion register as follows:
V = V
At reset, the DA conversion registers are cleared to “00
the DA output enable bits are cleared to “0”, and the P3
and P3
The DA output does not have buffers. Accordingly, connect an
external buffer when driving a low-impedance load.
Fig 53. Equivalent connection circuit of D/A converter (DA1)
Where V
DA
REF
1
/DA
1
conversion register
× n/256 (n = 0 to 255)
P3
2
1
0
pins become high impedance.
REF
/DA
Nov 14, 2005
or DA
1
0
and DA
/DA
is the reference voltage.
1
A
V
VSS
REF
2
1
pin by setting the DA output enable bit to
“1”
or P3
2
“0”
) with 8-bit resolution.
DA
1
/DA
MSB
1
output enable bit
Page 60 of 91
“0”
2
) must be set to “0” (input
“1”
2R
R
2R
R
16
0
”, and
/DA
1
2R
R
Fig 52. Block diagram of D/A converter
2R
R
R-2R resistor ladder
R-2R resistor ladder
DA
DA
1
2
conversion register (8)
conversion register (8)
2R
R
PRELIMINARY
Notice: This is not a final specification.
Some parametric limits are subject to change.
2R
R
DA
DA
1
2
output enable bit
output enable bit
2R
R
LSB
2R
2R
P3
P3
0
1
/DA
/DA
1
2