Datasheet

Data Sheet ADuCM360/ADuCM361
Rev. B | Page 13 of 24
Table 8. Typical Output RMS Noise Effective Number of Bits in Normal Mode, External Reference (2.5 V), Gain = 1, 2, 4, 8, and 16
Effective Number of Bits (ENOB) by Input Voltage Range and Gain
1
Update
Rate (Hz)
Chop/Sinc
Gain = 1,
±V
REF
,
ADCxMDE = 0x01
Gain = 2,
±500 mV,
ADCxMDE = 0x11
Gain = 4,
±250 mV,
ADCxMDE = 0x21
Gain = 8,
±125 mV,
ADCxMDE = 0x31
Gain = 16,
±62.5 mV,
ADCxMDE = 0x41
3.53 On/Sinc3 22.1
(19.4 p-p)
20.9
(18.2 p-p)
20.8
(18.1 p-p)
20.5
(17.7 p-p)
20.43
(17.7 p-p)
30 Off/Sinc3 20.7
(18.0 p-p)
19.4
(16.7 p-p)
19.2
(16.4 p-p)
19.1
(16.4 p-p)
18.82
(16.1 p-p)
50
Off/Sinc3
20.3
(17.6 p-p)
18.8
(16.1 p-p)
19.05
(16.3 p-p)
19.05
(16.3 p-p)
18.66
(15.9 p-p)
100 Off/Sinc3 19.9
(17.2 p-p)
18.4
(15.7 p-p)
18.6
(15.9 p-p)
18.6
(15.9 p-p)
18.32
(15.6 p-p)
488 Off/Sinc4 19.0
(16.3 p-p)
17.6
(14.9 p-p)
17.6
(14.9 p-p)
17.7
(14.9 p-p)
17.34
(14.6 p-p)
976 Off/Sinc4 18.6
(15.9 p-p)
17.1
(14.4 p-p)
17.1
(14.4 p-p)
17.1
(14.4 p-p)
16.66
(13.9 p-p)
1953 Off/Sinc4 17.9
(15.2 p-p)
16.6
(13.9 p-p)
16.4
(13.7 p-p)
16.55
(13.8 p-p)
16.15
(13.4 p-p)
3906 Off/Sinc4 15.1
(12.4 p-p)
13.8
(11.1 p-p)
13.8
(11.1 p-p)
13.8
(11.1 p-p)
13.77
(11.05 p-p)
1
RMS bits are calculated as follows: log
2
((2 × Input Range)/RMS Noise); peak-to-peak (p-p) bits are calculated as follows: log
2
((2 × Input Range)/(6.6 × RMS Noise)).
Table 9. Typical Output RMS Noise Effective Number of Bits in Normal Mode, External Reference (2.5 V), Gain = 32, 64, and 128
Effective Number of Bits (ENOB) by Input Voltage Range and Gain
1
Update
Rate (Hz) Chop/Sinc
Gain = 32,
±62.5 mV,
ADCxMDE =
0x49
Gain = 32,
±22.18 mV,
ADCxMDE =
0x51
Gain = 64,
±15.625 mV,
ADCxMDE =
0x59
Gain = 64,
±10.3125 mV,
ADCxMDE =
0x61
Gain = 128,
±7.8125 mV,
ADCxMDE =
0x69
Gain = 128,
±3.98 mV,
ADCxMDE =
0x71
3.53 On/Sinc3 19.6
(16.9 p-p)
19.3
(16.55 p-p)
18.4
(15.7 p-p)
18.4
(15.7 p-p)
17.8
(15.1 p-p)
17.1
(14.3 p-p)
30 Off/Sinc3 18.2
(15.5 p-p)
17.6
(14.9 p-p)
17.2
(14.5 p-p)
16.7
(14.0 p-p)
16.4
(13.7 p-p)
15.5
(12.8 p-p)
50 Off/Sinc3 17.8
(15.1 p-p)
17.7
(15.0 p-p)
16.8
(14.1 p-p)
16.65
(13.9 p-p)
16.1
(13.4 p-p)
15.35
(12.6 p-p)
100 Off/Sinc3 17.4
(14.6 p-p)
17.1
(14.35 p-p)
16.4
(13.7 p-p)
16.2
(13.4 p-p)
15.6
(12.85 p-p)
14.9
(12.2 p-p)
488 Off/Sinc4 16.4
(13.7 p-p)
16.0
(13.2 p-p)
15.4
(12.7 p-p)
15.1
(12.4 p-p)
14.6
(11.85 p-p)
14.0
(11.2 p-p)
976 Off/Sinc4 15.8
(13.1 p-p)
15.7
(13.0 p-p)
14.9
(12.2 p-p)
14.7
(12.0 p-p)
14.1
(11.4 p-p)
13.4
(10.6 p-p)
1953 Off/Sinc4 14.9
(12.1 p-p)
15.1
(12.3 p-p)
14.25
(11.5 p-p)
14.0
(11.3 p-p)
13.55
(10.8 p-p)
12.8
(10.1 p-p)
3906 Off/Sinc4 12.7
(10.0 p-p)
13.2
(10.4 p-p)
12.6
(9.9 p-p)
12.9
(10.2 p-p)
12.25
(9.5 p-p)
12.0
(9.3 p-p)
1
RMS bits are calculated as follows: log
2
((2 × Input Range)/RMS Noise); peak-to-peak (p-p) bits are calculated as follows: log
2
((2 × Input Range)/(6.6 × RMS Noise)).