Datasheet

AD7679
Rev. A | Page 13 of 28
POSITIVE DNL (LSB)
120
0
NUMBER OF UNITS
100
60
20
0
40
80
0.5 1.0 1.5
03085-0-011
2.0
Figure 11. Typical Positive DNL Distribution (424 Units)
NEGATIVE DNL (LSB)
180
–1.00
NUMBER OF UNITS
160
100
20
0
60
140
–0.75 –0.50 –0.25
03085-0-014
0
120
40
80
Figure 12. Typical Negative DNL Distribution (424 Units)
FREQUENCY (kHz)
0
0 30 60 240 270
AMPLITUDE (dB of Full Scale)
–40
–60
–100
–180
–80
–120
03085-0-012
–140
–20
–160
90 120 150 180 210
f
S
= 570kSPS
f
IN
= 10kHz
V
REF
= 4.096V
SNR = 98.5dB
THD = 115.8dB
SFDR = 117.4dB
S/(N+D) = 98.4dB
Figure 13. FFT (10 kHz Tone)
FREQUENCY (kHz)
105
1
SNR AND S/[N+D] (dB)
100
90
80
75
85
10 100 1000
03085-0-015
95
ENOB
S/(N+D)
SNR
16.5
17.0
15.5
16.0
14.5
15.0
14.0
ENOB (Bits)
Figure 14. SNR, S/(N+D), and ENOB vs. Frequency
FREQUENCY (kHz)
–60
1
THD, HARMONICS (dB)
–70
–100
–130
–120
–80
10 100 1000
03085-0-016
–90
–110
THD
THIRD
HARMONIC
SFDR
140
60
20
40
0
SFDR (dB)
120
80
100
SECOND
HARMONIC
Figure 15. THD, SFDR, and Harmonics vs. Frequency
INPUT LEVEL (dB)
–60
SNR REFERRED TO FULL SCALE (dB)
98
96
100
03085-0-017
SNR
–50 0–10–20–30–40
102
V
REF
= 4.096V
S/(N+D)
Figure 16. SNR and S/(N+D) vs. Input Level