A-D Converter; Fig. 2.5.1 A-D Converter Structure - Renesas 4513 User Manual

2.5 A-D converter

The 4513/4514 Group has an A-D converter with the 10-bit successive comparison method: 4 channels for
the 4513 Group, 8 channels for the 4514 Group.
This A-D converter can also be used as a comparator to compare analog voltages input from the analog
input pin with preset values.
This section describes the related registers, application examples using the A-D converter and notes.
Figure 2.5.1 shows the A-D converter block diagram.
IAP4
(P4 P4 )
—
0 3
Q2
OP4A
(P4 P4 )
—
0 3
(Note 3)
A /CMP0-
IN0
A /CMP0+
IN1
A /CMP1-
IN2
A /CMP1+
IN3
P4 /A
0 IN4
P4 /A
1 IN5
P4 /A
2 IN6
P4 /A
3 IN7
Notes 1: This switch is turned ON only when A-D converter is operating and generates the comparison voltage.
2: Writing/reading data to the comparator register is possible only in the comparator mode (Q2
The value of the comparator register is retained even when the mode is switched to the A-D conversion
mode (Q2 =0) because it is separated from the successive comparison register (AD). Also, the resolution in
3
the comparator mode is 8 bits because the comparator register consists of 8 bits.
3: The 4513 Group does not have ports P4

Fig. 2.5.1 A-D converter structure

TAQ2
TAQ1
TQ1A
TQ2A
3 Q2 2 Q2 1 Q2 0 Q1 Q1 Q1 Q1
3 2 1
3
A-D control circuit
1
Comparator
0
Q2
DAC
operation
signal
(Note 1)
V
SS
0
4513/4514 Group User's Manual
Register B (4)
Register A (4)
0
Instruction clock
1/6
Q2
3
0
1
Successive comparison
register (AD) (10)
3
10
0 1
Q2
3
DA converter
Comparator register (8)
(Note 2)
/A –P4 /A and the IAP4 and OP4A instructions.
IN4 3 IN7
APPLICATION
2.5 A-D converter
4 4
4
4
2
8 8
TALA TABAD
ADF
(1)
Q2
3
8
10
0 1
8
8 8
V
DD
=1).
3
TADAB
A-D interrupt
1
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