A-D CONVERTER
12.2 Block description
12.2 Block description
Figure 12.2.1 shows the block diagram of the A-D converter. Registers relevant to the A-D converter are
described below.
Selection of A-D conversion frequency
(1 ,1)
(1 ,0)
f
f
1
2
φAD
(0 ,1)
(0 ,0)
1/ 2
1/ 2
V
REF connection select bit
A-D conversion frequency (
select bits 1, 0
φAD)
0
1
VREF
Resistor ladder
Vref
network
A-D control register 2
A-D control register 1
AVSS
Comparator function select register 1
Comparator function select register 0
Selector
1
A-D control register 0
Selector
Control circuit
Successive
approximation register
Comparator result register 1
Comparator result register 0
A-D register 0
A-D register 1
A-D register 2
A-D register 3
A-D register 4
A-D register 5
A-D register 6
A-D register 7
A-D register 8
A-D register 9
A-D register 10
A-D register 11
Comparator
Decoder
Data bus (odd)
Data bus (even)
AN
AN
AN
AN
AN
AN
AN
AN
AN
AN
0
1
2
3
4
5
6
7
8
9
AN10
AN11
Selector
Fig. 12.2.1 Block diagram of A-D converter
7905 Group User’s Manual Rev.1.0
12-4
RENESAS [ RENESAS TECHNOLOGY CORP ]
