SX8722I070LF SEMTECH [Semtech Corporation], SX8722I070LF Datasheet - Page 19

• Manufacturer Part Number: SX8722I070LF
• Description: High gain acquisition for sensor interface
• Manufacturer: SEMTECH [Semtech Corporation]

5.3. ZoomingADC
The SX8722 core is the ZoomingADC™, the diagram below shows more in detail the architecture of this acquisition chain.
The block schematic above is separated in function boxes:
A. Input multiplexers
B. Programmable gain amplifiers
C. Offset cancellation
D. ADC
E. Measurement engine
ACS - Revision 4.2
©2008 Semtech Corp.
ADVANCED COMMUNICATIONS & SENSING
A
Routing of the input signal.
Routing of the reference.
Can be enabled/disabled separately.
Each PGA has programmable gain from 1 to 10.
Total PGA gain available = PGA1 x PGA2 x PGA3 = 1000.
Subtract or add a reference multiple to the input signal.
Can compensate up to 15 times the full scale signal.
Sigma-Delta ADC.
Offers several sampling frequencies.
Over sampling rates and elementary conversion combinations allow setting the ideal resolution for the ideal conversion
Manages up to 4 ZoomingADC™ configurations.
Updates the measured values.
time.
AC
AR
0
0
1
2
3
4
5
6
7
1
2
3
V
IN
C
B
f
S
V
REF
October 2008
+
-
PGA1
1 - 10
+
-
Figure 6. Acquisition chain architecture
OFF2
+
-
-5/5
5/5
...
1 - 2 - 5 - 10
PGA2
+
-
Page 19
+
-
+
-
0/12 to 127/12
PGA3
OFF3
-63/12
63/12
High gain acquisition for sensor interface
...
+
-
V
IN, ADC
+
-
D
ADC
f
S
E
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MEASUREMENT
www.semtech.com
SX8722
ENGINE