AD7980-EP

Rev. 0 | Page 9 of 12

180k

0

800C 800D 800E 800F

8009

8008

800B

800A

8003

8005

8004

8007

8006

2

0

0

0

33

829

0

27

0

1201

CODE IN HEX

140k

160k

100k

120k

60k

20k

80k

40k

38751

168591

52710

Figure 11. Histogram of a DC Input at the Code Center, REF = 5 V

70k

0

7FFF

8008

8001

8000

8003

8002

8005

8004

8007

8006

0

0

150

2

59691

5428

59404

3

93

CODE IN HEX

60k

50k

30k

10k

40k

20k

6295

Figure 12. Histogram of a DC Input at the Code Transition, REF = 5 V

100

80

85

90

95

2.25

5.25

REFERENCE VOLTAGE (V)

16

12

13

14

15

2.75

3.25

3.75

4.25

4.75

SNR

SINAD

ENOB

Figure 13. SNR, SINAD, and ENOB vs. Reference Voltage

60k

0

7FFA

8006

7FFC

7FFB

7FFE 7FFF

7FFD

8001

8000

8003 8004 8005

8002

0

0

0

0

539

16

14

502

CODE IN HEX

50k

30k

10k

40k

20k

32417

52212

31340

7225

6807

Figure 14. Histogram of a DC Input at the Code Center, REF = 2.5 V

95

85

87

89

92

91

93

94

86

88

90

–10

0

INPUT LEVEL (dB OF FULL SCALE)

–9

–8

–7

–6

–5

–4

–3

–2

–1

Figure 15. SNR vs. Input Level

–95

–125

–110

–115

–105

–100

–120

115

85

100

95

105

110

90

2.25

5.25

REFERENCE VOLTAGE (V)

2.75

3.25

3.75

4.25

4.75

THD

SFDR

Figure 16. THD, SFDR vs. Reference Voltage