Datasheet

Data Sheet ADuCM360/ADuCM361
Rev. B | Page 11 of 24
Table 4. Typical Output RMS Noise Effective Number of Bits in Normal Mode, Internal Reference (1.2 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 21.1
(18.4 p-p)
21.1
(18.4 p-p)
21.1
(18.3 p-p)
20.8
(18.1 p-p)
20.7
(18.0 p-p)
30 Off/Sinc3 20.1
(17.4 p-p)
19.5
(16.8 p-p)
19.6
(16.9 p-p)
19.4
(16.6 p-p)
19.1
(16.4 p-p)
50
Off/Sinc3
19.3
(16.6 p-p)
19.25
(16.5 p-p)
19.2
(16.5 p-p)
19.0
(16.3 p-p)
18.7
(16.0 p-p)
100 Off/Sinc3 18.7
(16.0 p-p)
18.66
(15.9 p-p)
18.75
(16.0 p-p)
18.6
(15.9 p-p)
18.3
(15.6 p-p)
488 Off/Sinc4 17.9
(15.2 p-p)
17.7
(15.0 p-p)
17.8
(15.1 p-p)
17.55
(14.8 p-p)
17.3
(14.5 p-p)
976 Off/Sinc4 17.4
(14.7 p-p)
17.2
(14.5 p-p)
17.2
(14.5 p-p)
17.2
(14.4 p-p)
16.8
(14.1 p-p)
1953 Off/Sinc4 16.9
(14.2 p-p)
16.6
(13.9 p-p)
16.7
(14.0 p-p)
16.55
(13.8 p-p)
16.3
(13.6 p-p)
3906 Off/Sinc4 15.1
(12.4 p-p)
14.8
(12.0 p-p)
14.9
(12.2 p-p)
14.8
(12.1 p-p)
14.6
(11.9 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 5. Typical Output RMS Noise Effective Number of Bits in Normal Mode, Internal Reference (1.2 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 19.8
(17.1 p-p)
19.4
(16.7 p-p)
18.7
(16.0 p-p)
18.5
(15.8 p-p)
18.0
(15.3 p-p)
17.2
(14.5 p-p)
30 Off/Sinc3 18.2
(15.5 p-p)
17.75
(15.0 p-p)
17.3
(14.6 p-p)
17.0
(14.25 p-p)
16.45
(13.7 p-p)
15.6
(12.9 p-p)
50 Off/Sinc3 18.0
(15.2 p-p)
17.5
(14.8 p-p)
16.93
(14.2 p-p)
16.6
(13.86 p-p)
16.2
(13.5 p-p)
15.3
(12.55 p-p)
100 Off/Sinc3 17.4
(14.7 p-p)
17.1
(14.35 p-p)
16.4
(13.7 p-p)
16.2
(13.5 p-p)
15.6
(12.9 p-p)
15.0
(12.2 p-p)
488 Off/Sinc4 16.4
(13.7 p-p)
16.0
(13.3 p-p)
15.4
(12.7 p-p)
15.1
(12.4 p-p)
14.6
(11.9 p-p)
13.8
(11.0 p-p)
976 Off/Sinc4 15.9
(13.2 p-p)
15.6
(12.85 p-p)
14.91
(12.2 p-p)
14.8
(12.0 p-p)
14.2
(11.5 p-p)
13.4
(10.75 p-p)
1953 Off/Sinc4 15.1
(12.4 p-p)
15.05
(12.3 p-p)
14.4
(11.6 p-p)
14.1
(11.4 p-p)
13.6
(10.9 p-p)
13.0
(10.2 p-p)
3906 Off/Sinc4 13.2
(10.5 p-p)
14.0
(11.3 p-p)
13.1
(10.4 p-p)
13.8
(11.1 p-p)
12.8
(10.1 p-p)
12.5
(9.75 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)).