MAX11321 Datasheet, PDF (34/37 Pages) Maxim Integrated Products – 1Msps, 10-/12-Bit, 4-/8-/16-Channel ADCs with Post-Mux External Signal Conditioning Access

MAX11321–MAX11328
1Msps, 10-/12-Bit, 4-/8-/16-Channel ADCs with
Post-Mux External Signal Conditioning Access
Choosing a Reference
For devices using an external reference, the choice of the
reference determines the output accuracy of the ADC.
An ideal voltage reference provides a perfect initial accu-
racy and maintains the reference voltage independ­ ent
of changes in load current, temperature, and time. The
following parameters need to be considered in selecting
a reference:
U Initial voltage accuracy
U Temperature drift
U Current source capability
U Current sink capability
U Quiescent current
U Noise. See Table 16.
INPUT 1
500I
VDC
INPUT 2
500I
VDC
+5V
0.1µF
10µF
V_DD
100pF
500I
0.1µF
10µF
4
5
MAX4430
3
2
1
10I
-5V
470pF
COG
CAPACITOR
0.1µF
10µF
COG
CAPACITOR
470pF
+5V
10µF
0.1µF
10µF
VDD
OVDD
AGND
AOP
AON
MAX11321–MAX11328
AIP
AIN0
AIN
SCLK
AIN1
DOUT
INPUT 2
AIN15
CS
REF
DIN
GND
100pF
500I
4
5
MAX4430
3
2
1
10I
-5V
0.1µF
10µF
7 _OUTF
IN ²
6
OUTS
0.1µF
MAX6126
4 _GNDS
1
NR
3
GND
VOVDD
0.1µF
10µF
SCLK
MISO
CPU
SS
MOSI
+5V
1µF
0.1µF
0.1µF
Figure 13. Typical Application Circuit
Maxim Integrated
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