Datasheet

AD9859
Rev. A | Page 23 of 24
SUGGESTED APPLICATION CIRCUITS
03375-0-015
LPF
AD9859
REFCL
K
RF/IF INPUT
MODULATED/
DEMODULATED
SIGNAL
Figure 25. Synchronized LO for Upconversion/Down Conversion
03375-0-016
FILTER
PHASE
COMPARATOR
LOOP
FILTER
AD9859
TUNING
WORLD
REF
SIGNAL
VCO
Figure 26. Digitally Programmable Divide-by-N Function in PLL
03375-017
CRYSTAL
FREQUENCY
TUNING
WORD
PHASE
OFFSET
WORD 2
I/I
BASEBAND
FREQUEN
C
Y
TUNING
WORD
PHASE
OFFSET
WORD 1
Q/Q
BASEBAND
SYNC IN
AD9859 DDS
REFCLK
REFCLK
REFCLK
LPF
SYNC OUTCRYSTAL OUT
AD9859 DDS
IOUT
IOUT
LPF
IOUT
IOUT
RF OUT
Figure 27. Two AD9859s Synchronized to Provide I and
Q Carriers with Independent Phase Offsets for Nulling