AD9915 AD [Analog Devices], AD9915 Datasheet - Page 14

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

AD9915
Figure 16. Absolute Phase Noise Curves of Normalized REF CLK Source to
–100
–110
–120
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–150
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–170
–180
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–60
–70
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–90
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–90
0.5
0.4
0.3
0.2
0.1
0
10
500
10
DDS Output at 978.5 MHz (SYSCLK = 2.5 GHz)
Figure 18. Power Supply Current vs. SYSCLK
100
100
Figure 17. Residual Phase Noise Curves
1000
NORMALIZED
REF CLK SOURCE
1k
978MHz
1k
FREQUENCY OFFSET (Hz)
FREQUENCY OFFSET (Hz)
978MHz
SYSTEM CLOCK (MHz)
305MHz
10k
10k
1500
100k
100k
497MHz
123MHz
3.3V ANALOG
1.8V ANALOG
1.8V DIGITAL
3.3V DIGITAL
1M
1M
2000
10M
10M
100M
100M
2500
Rev. A | Page 14 of 48
Figure 19. Absolute Phase Noise Curves of DDS Output Using Internal PLL at
Figure 20. Residual PN vs. Absolute PN Measurement Curves at 978.5 MHz
Figure 21. Residual Phase Noise vs. Normalized Absolute REF CLK Source
–100
–110
–120
–130
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–160
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–160
–170
–180
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–170
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–90
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–70
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–80
–90
10
10
10
100
100
100
978MHz RESIDUAL
978MHz RESIDUAL
Phase Noise at 978.5 MHz
1k
1k
1k
978MHz ABSOLUTE
FREQUENCY OFFSET (Hz)
FREQUENCY OFFSET (Hz)
FREQUENCY OFFSET (Hz)
978MHz ABSOLUTE
978MHz
2.5 GHz Operation
305MHz
10k
10k
10k
123MHz
100k
100k
100k
497MHz
1M
1M
1M
Data Sheet
10M
10M
10M
100M
100M
100M