AD9864 Datasheet, PDF (36/44 Pages) Analog Devices – IF Digitizing Subsystem

AD9864
which low level spurs can degrade the AD9864’s sensitivity
performance.
Despite the many spurs, sweet spots in the LO frequency are
generally wide enough to accommodate the maximum signal
bandwidth of the AD9864. As evidence of this property,
Figure 68 shows that the in-band noise is quite constant for LO
frequencies ranging from 70 MHz to 71 MHz.
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LO FREQUENCY (MHz)
Figure 66. Total In-Band Noise + Spur Power with No Signal Applied as a Function of the LO Frequency (fCLK = 18 MHz and Output Signal Bandwidth = 150 kHz)
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LO FREQUENCY (MHz)
Figure 67. Same as Figure 66 Excluding LO Frequencies Known to Produce Large In-Band Spurs
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