Datasheet

AD6645
Rev. D | Page 10 of 24
FREQUENCY (MHz)
SNR (dB)
72.0
72.5
73.0
73.5
74.0
74.5
75.0
75.5
0 10203040506070
T = –40°C
T = +85°C
T = +25°C
ENCODE = 80MSPS @ AIN = –1dBFS
TEMP = –40°C, +25°C, +85°C
02647-016
Figure 10. Signal-to-Noise Ratio (SNR) vs. Frequency
ANALOG INPUT FREQUENCY (MHz)
WORST-CASE HARMONIC (dBc)
80
82
84
86
88
90
92
94
T = +25°C
T = –40°C, +85°C
ENCODE = 80MSPS @ AIN = –1dBFS
TEMP = –40°C, +25°C, +85°C
0 10203040506070
0
2647-017
Figure 11. Worst-Case Harmonics vs. Analog Input Frequency
ANALOG FREQUENCY (MHz)
SNR (dB)
70
71
72
73
74
75
76
0 20 40 60 80 100 120 140 160 180 200
ENCODE = 80MSPS @ AIN = –1dBFS
TEMP = 25°C
02647-018
Figure 12. Signal-to-Noise Ratio (SNR) vs. Analog Frequency (IF)
ANALOG FREQUENCY (MHz)
HARMONICS (dBc)
60
65
70
80
90
100
75
85
95
WORST OTHER SPUR
HARMONICS
(SECOND, THIRD)
ENCODE = 80MSPS @ AIN = –1dBFS
TEMP = 25°C
0 20 40 60 80 100 120 140 160 180 200
02647-019
Figure 13. Harmonics vs. Analog Frequency (IF)
ANALOG INPUT POWER LEVEL (dBFS)
WORST-CASE SPURIOUS (dBFS AND dBc)
0
10
20
30
40
50
60
70
80
90
100
110
dBc
120
dBFS
ENCODE = 80MSPS
AIN = 30.5MHz
SFDR = 90dB
REFERENCE LINE
–90 –80 –70 –60 –50 –40 –30 –20 –10 0
02647-020
Figure 14. Single-Tone SFDR @ 30.5 MHz
ANALOG INPUT POWER LEVEL (dBFS)
WORST CASE SPURIOUS (dBFS AND dBc)
0
10
20
30
40
50
60
70
80
90
100
110
dBc
120
dBFS
–90 –80 –70 –60 –50 –40 –30 –20 –10 0
SFDR = 90dB
REFERENCE LINE
ENCODE = 80MSPS
AIN = 69.1MHz
0
2647-021
Figure 15. Single-Tone SFDR @ 69.1 MHz