Datasheet

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22
21
20
19
18
17
16
15
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Decimation Ratio =
f
MOD
f
DATA
0 500 1000 1500 2000
PGA4
ENOB (rms)
PGA1
PGA2
PGA16
PGA8
PGA32
PGA64
PGA128
Sinc
2
Filter
22
21
20
19
18
17
16
15
14
13
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0 500 1000 1500 2000
ENOB (rms)
1500
Decimation Ratio =
f
MOD
f
DATA
Fast Settling Filter
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
V
IN
(V)
−
2.5
−
1.5 0.5
−
0.5 1.5 2.5
Noise (rms, ppm of FS)
130
120
110
100
90
80
70
60
50
40
30
20
10
0
Frequency of CM Signal (Hz)
1 10 100 1k 10k 100k
CMRR (dB)
50
0
−
50
−
100
−
150
−
200
Offset (ppm of FS)
PGA1
PGA128
PGA64
Temperature (

C)
−
50
−
30 10
−
10 30 50 70 90
PGA16
120
110
100
90
80
70
60
50
40
30
20
10
0
Frequency of Power Supply (Hz)
1 10 1k100 10k 100k
PSRR (dB)
ADS1218
SBAS187C – SEPTEMBER 2001 – REVISED SEPTEMBER 2005
TYPICAL CHARACTERISTICS (continued)
AV
DD
= +5V, DV
DD
= +5V, f
OSC
= 2.4576MHz, PGA = 1, R
DAC
= 150k Ω , V
REF
≡ (REF IN+) – (REF IN–) = +2.5V, and
f
DATA
= 10Hz, unless otherwise specified.
EFFECTIVE NUMBER OF BITS FAST SETTLING FILTER
vs DECIMATION RATIO EFFECTIVE NUMBER OF BITS vs DECIMATION RATIO
Figure 5. Figure 6.
NOISE vs INPUT SIGNAL CMRR vs FREQUENCY
Figure 7. Figure 8.
PSRR vs FREQUENCY OFFSET vs TEMPERATURE
Figure 9. Figure 10.
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