Datasheet

AD9280
–17–
Figures 35–38 combine the dual-tone SFDR as well as single
tone SFDR and SNR performance at IF frequencies of 45 MHz,
70 MHz, 85 MHz and 135 MHz. Note, the SFDR vs. ampli-
tude data is referenced to dBFS while the single tone SNR data
INPUT POWER LEVEL – dBFS
70
0
–0.5 –40–5
WORST CASE SPURIOUS – dBFS
SNR – dBc
–10 –15 –20 –25 –30 –35
60
40
30
20
10
50
SNR
DUAL TONE SFDR
SINGLE TONE SFDR
CLK = 25.7MHz
SINGLE TONE = 45.5MHz
DUAL TONE F1 = 44.5MHz
F2 = 45.5MHz
Figure 35. SNR/SFDR for IF @ 45 MHz
INPUT POWER LEVEL – dBFS
70
0
–0.5 –40–5
WORST CASE SFDR – dBFS
SNR – dBc
–10 –15 –20 –25 –30 –35
60
40
30
20
10
50
SNR
DUAL TONE SFDR
SINGLE TONE SFDR
CLK = 31.1MHz
SINGLE TONE = 70.5MHz
DUAL TONE F1 = 69.5MHz
F2 = 70.5MHz
Figure 36. SNR/SFDR for IF @ 70 MHz
is referenced to dBc. The AD9280 was operated in the differen-
tial mode (via transformer) with a 1 V span. The analog sup-
ply (AVDD) and the digital supply (DRVDD) were set to +5 V
and 3.3 V, respectively.
INPUT POWER LEVEL – dBFS
80
0
–0.5 –40–5
WORST CASE SPURIOUS – dBFS
SNR – dBc
–10 –15 –20 –25 –30 –35
70
40
30
20
10
60
50
SNR
DUAL TONE SFDR
SINGLE TONE SFDR
CLK = 30.9MHz
SINGLE TONE = 85.5MHz
DUAL TONE F1 = 84.5MHz
F2 = 85.5MHz
Figure 37. SNR/SFDR for IF @ 85 MHz
INPUT POWER LEVEL – dBFS
70
0
–0.5 –40–5
WORST CASE SPURIOUS – dBFS
SNR – dBc
–10 –15 –20 –25 –30 –35
60
40
30
20
10
50
SNR
SINGLE TONE SFDR
FS = 32MHz
SINGLE TONE = 135.5MHz
F1 = 134.5MHz
F2 = 135.5MHz
DUAL TONE SFDR
Figure 38. SNR/SFDR for IF @ 135 MHz
REV. E