Datasheet
REV.
AD7665
–10–
–0
–20
–40
–60
–80
–100
–120
–140
–160
–180
0 57 114 171 228 285
AMPLITUDE – dB OF FULL SCALE
FREQUENCY – kHz
4096 POINT FFT
FS = 571kHz
f
IN
= 45kHz, –0.5dB
SNR = 90.1 dB
SINAD = 89.7dB
THD = –100.1dB
SFDR = 102.3dB
TPC 7. FFT Plot
100
95
90
85
80
75
70
1 10 100 1000
16.0
15.5
15.0
14.5
14.0
13.5
13.0
SNR AND S/[N +D] – dB
ENOB – Bits
FREQUENCY – kHz
SNR
SINAD
ENOB
TPC 8. SNR, S/(N+D), and ENOB vs. Frequency
92
90
88
86
–80 –70 –60 –50 –40 –30 –20 –10 0
SNR – (REFERRED TO FULL SCALE) – dB
INPUT LEVEL – dB
TPC 9. SNR vs. Input Level
96
93
90
87
84
–98
–100
–102
–104
–55 –35 –15 5 25 45 65 85 105 125
SNR – dB
THD – dB
TEMPERATURE – C
THD
SNR
TPC 10. SNR, THD vs. Temperature
THD
SECOND HARMONIC
THIRD HARMONIC
SFDR
–60
–65
–70
–75
–80
–85
–90
–95
–100
–105
–110
–115
110
105
100
95
90
85
80
75
70
65
60
1 10 100 1000
THD, HARMONICS – dB
SFDR – dB
FREQUENCY – kHz
TPC 11. THD, Harmonics, and SFDR vs. Frequency
–60
–70
–80
–90
–100
–110
–120
–130
–140
–150
–60 –50 –40 –30 –20 –10 0
THD, HARMONICS – dB
INPUT LEVEL – dB
THD
THIRD HARMONIC
SECOND HARMONIC
TPC 12. THD, Harmonics vs. Input Level
C