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 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

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

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 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

19.8

(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