Datasheet

AD6644
Rev. D | Page 9 of 24
TYPICAL PERFORMANCE CHARACTERISTICS
FREQUENCY (MHz)
(dBFS)
0
–120
–130
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
ENCODE = 65MSPS
AIN = 2.2MHz @ –1dBFS
SNR = 74.5dB
SFDR = 92dBc
0 5 10 15 20 25 30
00971-004
Figure 4. Single Tone at 2.2. MHz
FREQUENCY (MHz)
0
–120
–130
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
(dBFS)
0 5 10 15 20 25 30
ENCODE = 65MSPS
AIN = 15.5MHz @ –1dBFS
SNR = 74dB
SFDR = 90dBc
00971-005
Figure 5. Single Tone at 15.5 MHz
FREQUENCY (MHz)
0
–120
–130
–110
–100
–90
–80
–70
–60
–50
–40
–30
–20
–10
(dBFS)
ENCODE = 65MSPS
AIN = 30MHz @ –1dBFS
SNR = 73.5dB
SFDR = 85dBc
0 5 10 15 20 25 30
00971-006
Figure 6. Single Tone at 30 MHz
FREQUENCY (MHz)
SNR (dB)
74.5
73.5
72.5
72.0
74.0
73.0
75.0
T = –25°C
T = +25°C
T = +85°C
0 5 10 15 20 25 30
ENCODE = 65MSPS, AIN = –1dBFS
TEMP = –25°C, +25°C, +85°C
00971-007
Figure 7. Noise vs. Analog Frequency (Nyquist)
ANALOG INPUT FREQUENCY (MHz)
WORST-CASE HARMONIC (dBc)
92
86
82
80
90
84
88
94
0 5 10 15 20 25 30
T = –25°C, +85°C
T = +25°C
ENCODE = 65MSPS, AIN = –1dBFS
TEMP = –25°C, +25°C, +85°C
00971-008
Figure 8. Harmonics vs. Analog Frequency (Nyquist)
ANALOG FREQUENCY (MHz)
SNR (dB)
74
71
69
68
73
70
72
75
AIN = –1dBFS
ENCODE = 65MSPS
LOW NOISE ANALOG SOURCE
PHASE NOISE OF ANALOG SOURCE
DEGRADES PERFORMANCE
0 102030405060708090100
0
0971-009
Figure 9. Noise vs. Analog Frequency (IF)