MAX11129_12 Datasheet, PDF (33/36 Pages) Maxim Integrated Products – 3Msps, Low-Power, Serial 12-/10-Bit,8-/16-Channel ADCs

MAX11129–MAX11132
3Msps, Low-Power, Serial 12-/10-Bit,
8-/16-Channel ADCs
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. The MAX6033 and MAX6043 are also excellent
reference choices (Figure 13).
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 _470pF
CAPACITOR
+5V
10µF
0.1µF
10µF
100pF
500I
4
5
MAX4430
3
2
1
10I
-5V
0.1µF
10µF
0.1µF
VDD
OVDD
AGND
MAX11129–MAX11132
AIN0
AIN1
INPUT 2
AIN15
REF
GND
SCLK
DOUT
CS
DIN
VOVDD
0.1µF
10µF
SCLK
MISO
CPU
SS
MOSI
7 _OUTF
6
OUTS
4
GNDS
3
GND
MAX6126
IN ²
1
NR
+5V
1µF
0.1µF
0.1µF
Figure 13. Typical Application Circuit
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