MAX1403_02 Datasheet, PDF (27/36 Pages) Maxim Integrated Products – +3V, 18-Bit, Low-Power, Multichannel, Oversampling (Sigma-Delta) ADC

+3V, 18-Bit, Low-Power, Multichannel,
Oversampling (Sigma-Delta) ADC
Table 16b. Noise vs. Gain and Output Data Rate—Buffered Mode, V_REF = 1.25V,
f_CLKIN = 2.4576MHz
OUTPUT
DATA
RATE
(sps)
-3dB
FREQ.
(Hz)
x1
50
13.1
5.72
60
15.7
6.29
300
78.6
80.6
600
157.2
436
100
26.2
5.82
120
31.4
6.01
600
157.2
77.7
1200
314.4
434
200
52.4
5.82
240
62.9
6.17
1200
314.4
79.0
2400
628.8
439
400
104.8
5.60
480
125.7
6.18
2400
628.8
76.3
4800
1258
455
TYPICAL OUTPUT NOISE (µV_RMS)
FOR VARIOUS PROGRAMMABLE GAINS
x2
x4
x8
x16
x32
x64
3.21
2.10
1.41
1.42
1.44
1.38
3.57
2.30
1.55
1.61
1.56
1.49
39.8
19.3
10.2
6.14
4.25
3.03
225
116
57.1
28.8
15.0
8.70
3.35
2.08
1.43
1.37
1.36
1.35
3.65
2.27
1.51
1.51
1.50
1.50
40.1
20.2
10.6
5.93
4.19
3.54
222
111
57.0
28.3
14.8
8.37
3.07
1.87
1.26
1.20
1.18
1.15
3.54
2.09
1.45
1.30
1.27
1.31
41.1
19.8
10.5
5.68
3.68
3.14
226
111
57.9
28.7
15.4
8.26
3.10
1.85
1.32
1.24
1.25
1.19
3.47
2.02
1.38
1.37
1.29
1.33
39.3
20.8
9.83
5.92
3.92
3.92
225
114
57.1
29.9
14.5
8.13
x128
1.34
1.56
3.52
5.99
1.31
1.47
3.23
5.81
1.17
1.29
2.99
5.32
1.21
1.33
3.07
5.55
BIT
STATUS
MF1:MF0 = 0
FS1:FS0 = 0
FS1:FS0 = 1
FS1:FS0 = 2
FS1:FS0 = 3
MF1:MF0 = 1
FS1:FS0 = 0
FS1:FS0 = 1
FS1:FS0 = 2
FS1:FS0 = 3
MF1:MF0 = 2
FS1:FS0 = 0
FS1:FS0 = 1
FS1:FS0 = 2
FS1:FS0 = 3
MF1:MF0 = 3
FS1:FS0 = 0
FS1:FS0 = 1
FS1:FS0 = 2
FS1:FS0 = 3
20
19
18
17
16
15
14
13
12
11
10
1
a) BUFF = 0
CLK = 1
FS1: FS0 = 0 OR 1
FS1: FS0 = 2
FS1: FS0 = 3
CLK = 1
BUFF = 0
2 4 8 16 32 64 128 256
GAIN (V/V)
Figure 7. Effective Resolution vs. Gain and Notch Frequency
20
19
18
17
16
15
14
13
12
11
10
1
b) BUFF = 1
FS1: FS0 = 0 OR 1
FS1: FS0 = 2
FS1: FS0 = 3
CLK = 1
BUFF = 1
2 4 8 16 32 64 128 256
GAIN (V/V)
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