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 Gain1

Update

Rate (Hz)

Chop/Sinc

Gain = 1,

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

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 Gain1

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