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dc1984af
DEMO MANUAL DC1984A
measurement equipment anD setup
The LTC5510 is a wideband active mixer IC with very high
linearity. Accuracy of its performance measurement is
highly dependent on equipment setup and measurement
technique. The recommended measurement setups are
presented in Figure 4, Figure 5 and Figure 6. The following
precautions should be observed:
1. Use high performance signal generators with low har-
monic output and low phase noise, such as the Rohde
& Schwarz SME06. Filters at the signal generators’
outputs may also be used to suppress higher order
harmonics.
2. A high quality RF power combiner which provides
broadband 50Ω termination on all ports and has good
port-to-port isolation should be used, such as the Mini-
Circuits ZFSC-2-372-S+.
3. Use high performance amplifiers with high IP3 and
high reverse isolation, such as the Mini-Circuits ZHL-
1042J, on the outputs of the RF signal generators to
improve source isolation to prevent the sources from
modulating each other and generating intermodulation
products.
4. Use attenuator pads with good V
SWR
on the demon-
stration circuit’s input and output ports to improve
source and load match to reduce reflections, which
may degrade measurement accuracy.
5. A high dynamic range spectrum analyzer, such as
the Rohde & Schwarz FSEM30, should be used for
linearity measurement.
NETWORK
ANALYZER
5V DC
POWER
SUPPLY
+
–
50Ω
TERMINATION
50Ω
TERMINATION
Figure 4. Proper Equipment Setup for Return Loss Measurements