5.0 V
3.9 V
2.5 V
1.1 V
VA
AINx+
3.9 V
2.5 V
1.1 V
AINx-
Full-Scale
Differential
Input Level =
(AINx+) - (AINx-) = 5.6 V
PP
= 1.98 V
RMS
Figure 9. Full-Scale Input
5.2.2 ADC3 Analog Input
ADC3 accommodates differential as well as single-ended inputs. In Single-Ended mode, an in-
ternal MUX selects from up to 4 single-ended inputs.
AIN5A
Single-Ended Input Filter
ADC3
AIN5_MUX
ADC3 SINGLE
AIN5B
Single-Ended Input Filter
1
0
1
50
AIN5+/-
0
Differential
Input Filter
+
AIN5
-
49
0
VQ
1
AIN6_MUX
1
0
1
52
AIN6+/-
0
Differential
Input Filter
+
AIN6
-
51
0
VQ
AIN6A
1
Single-Ended Input Filter
AIN6B
Single-Ended Input Filter
Figure 10. ADC3 Input Topology
Hardware Mode
Single-Ended mode is selected using a pull-up on the ADC_SDOUT/ADC3_SINGLE pin during
startup. Analog input selection is then made via the AINx_MUX pins. See Tables 3-4 below for
ADC3 setup options. Refer to Figure 10 on page 28 for the internal ADC3 analog input topology.
28
DS646PP2
CIRRUS [ CIRRUS LOGIC ]
