AD9915 AD [Analog Devices], AD9915 Datasheet - Page 13

• Manufacturer Part Number: AD9915
• Description: 2.5 GSPS Direct Digital Synthesizer with 12-Bit DAC
• Manufacturer: AD [Analog Devices]

Data Sheet
–100
–10
–20
–30
–40
–50
–60
–70
–80
–10
–20
–30
–40
–50
–60
–70
–80
–10
–20
–30
–40
–50
–60
–70
–80
–90
0
0
0
0
0
START 0Hz
SYSCLK = 1.5GHz
SYSCLK = 1.6GHz
SYSCLK = 1.7GHz
SYSCLK = 1.8GHz
SYSCLK = 1.9GHz
SYSCLK = 2.0GHz
SYSCLK = 2.1GHz
SYSCLK = 2.2GHz
SYSCLK = 2.3GHz
SYSCLK = 2.4GHz
SYSCLK = 2.5GHz
Figure 12. Wideband SFDR vs. Normalized f
Figure 11. Wideband SFDR vs. Normalized f
0.05
0.05
Figure 10. Wideband SFDR at 978.2 MHz,
SYSCLK = 2.5 GHz (SYSCLK PLL Bypassed)
0.10
0.10
SYSCLK = 2.5 GHz to 2.5 GHz
SYSCLK = 2.5 GHz
0.15
0.15
125MHz/DIV
f
f
0.20
0.20
C
C
/
/
f
f
S
S
0.25
0.25
0.30
0.30
STOP 1.25GHz
OUT
OUT
0.35
0.35
,
0.40
0.40
Rev. A | Page 13 of 48
Figure 15. Absolute Phase Noise Curves of DDS Output at 2.5 GHz Operation
Rohde & Schwarz SMA100 Signal Generator at 2.5 GHz Buffered by Series
Figure 14. Absolute Phase Noise of REF CLK Source Driving
–100
–100
–110
–120
–130
–140
–150
–160
–170
–100
–110
–120
–130
–140
–150
–160
–170
–10
–20
–30
–40
–50
–60
–70
–80
–90
–70
–80
–90
–70
–80
–90
0
10
10
CENTER 978.214MHz
Figure 13. Narrow-Band SFDR at 978.2 MHz,
100
100
SYSCLK = 2.5 GHz (SYSCLK PLL Bypassed)
1k
1k
978MHz
305MHz
FREQUENCY OFFSET (Hz)
FREQUENCY OFFSET (Hz)
ADCLK925
10k
10k
50kHz/DIV
497MHz
100k
100k
123MHz
SMA
1M
1M
SPAN 500kHz
SMA AND
ADCLK925
10M
10M
AD9915
AD9915
100M
100M