SAB80C517-M16 SIEMENS [Siemens Semiconductor Group], SAB80C517-M16 Datasheet - Page 88

• Manufacturer Part Number: SAB80C517-M16
• Description: 8-Bit CMOS Single-Chip Microcontroller
• Manufacturer: SIEMENS [Siemens Semiconductor Group]

If DAPR (.3-.0) or DAPR (.7-.4) = 0, the internal reference voltages correspond to the external
reference voltages
If
(
If the external reference voltages
applied, then the following internal reference voltages
be adjusted via the special function register DAPR.
Table 7-7
Adjustable Internal Reference Voltages
Step
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
The programmability of the internal reference voltages allows adjusting the internal voltage range
to the range of the external analog input voltage or it may be used to increase the resolution of the
converted analog input voltage by starting a second conversion with a compressed internal
reference voltage range close to the previously measured analog value. Figures 7-30 and 7-31
illustrate these applications.
Semiconductor Group
V
V
AINPUT
AINPUT
is the analog input voltage).
>
V
INTAREF
, the conversion result is 0FF H , if
V
AGND
DAPR (.3-.0)
DAPR (.7-.4)
0000
0001
0010
0011
0100
0101
0110
0111
1000
1001
1010
1011
1100
1101
1110
1111
and
V
AREF
V
, respectively.
AGND
= 0 V and
89
V
0.0
0.3125
0.625
0.9375
1.25
1.5625
1.875
2.1875
2.5
2.8125
3.125
3.4375
3.75
–
–
–
V
INTAGND
V
AREF
AINPUT
On-Chip Peripheral Components
V
INTAGND
= + 5 V (with respect to
< V
INTAGND
and
V
INTAREF
, the conversion result is 00 H
V
5.0
–
–
–
1.25
1.5625
1.875
2.1875
2.5
2.8125
3.125
3.4375
3.75
4.0625
4.375
4.6875
shown in table 7-7 can
INTAREF
V
SS
and
V
CC
) are