Datasheet

Data Sheet AD9257
Rev. A | Page 15 of 40
120
0
SNR/SFDR (dBFS/dBc)
INPUT AMPLITUDE (dBFS)
SFDRFS
SFDR
SNRFS
SNR
0
20
40
60
80
100
–90 –80 –70 –60 –50
–40 –30 –20 –10
10206-026
Figure 27. SNR/SFDR vs. Analog Input Level, f
IN
= 9.7 MHz, f
SAMPLE
= 40 MSPS
105
20 30 40
SNR/SFDR (dBFS/dBc)
SAMPLE FREQUENCY (MSPS)
70
75
80
85
90
95
100
SFDR
SNRFS
10206-027
25 35
Figure 28. SNR/SFDR vs. Encode, f
IN
= 19.7 MHz, CLK Divider = 4
105
70
–40 85
SNR/SFDR (dBFS/dBc)
TEMPERATURE (°C)
75
80
85
90
95
100
–15 10 35 60
SFDR (dBc)
SNR (dBFS)
10206-028
Figure 29. SNR/SFDR vs. Temperature, f
IN
= 9.7 MHz, f
SAMPLE
= 40 MSPS
110
100
0
0 200
SNR/SFDR (dBFS/dBc)
INPUT FREQUENCY (MHz)
10206-029
70
10
20
30
40
50
60
80
90
100 120 1408020 40 60 180160
SFDR (dBc)
SNR (dBFS)
Figure 30. SNR/SFDR vs. f
IN
, f
SAMPLE
= 40 MSPS
30 40
25 35
105
20
SNR/SFDR (dBFS/dBc)
SAMPLE FREQUENCY (MSPS)
70
75
80
85
90
95
100
10206-030
SFDR
SNRFS
Figure 31. SNR/SFDR vs. Encode, f
IN
= 30.5 MHz, CLK Divider = 4
0
50,000
100,000
150,000
200,000
250,000
300,000
350,000
450,000
400,000
500,000
N – 10
N – 9 N – 8 N – 7 N – 6 N – 5 N – 4 N – 3 N – 2
N – 1
N
N + 1 N + 2 N + 3 N + 4 N + 5 N + 6 N + 7
N + 8 N + 9
N + 10
NUMBER OF HITS
OUTPUT CODE
10206-031
0.91 LSB RMS
Figure 32. Input-Referred Noise Histogram, f
SAMPLE
= 40 MSPS