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NI Digital Waveform Generator/Analyzer Getting Started Guide
Note
If you are designing a custom cabling solution with connector (779157-01)
and the NI SHB12X-B12X cable (192344-01), the NI 656
x
pinout is reversed at the
end connector. Refer to Figure 18 for an illustration of the pinout at the end
connector.
Wiring for Common Measurements
Dynamic generation and dynamic acquisition are two categories of applications that you can
create for NI digital waveform generator/analyzers. This section provides information about the
general wiring considerations for each type of application. Both examples use the NI 655
x
and
the NI CB-2162 for signal termination.
Dynamic Generation
When performing dynamic generation, an NI digital waveform generator/analyzer
(NI 654
x
/655
x
) generates data through a matched impedance system that consists of a 50
Ω
output impedance, a 50
Ω
cable, and a 50
Ω
accessory. Figure 12 shows a diagram of such a
system, using the NI 655
x
as an example. Depending on the loading of the peripheral device, you
may need additional parallel termination resistance at the destination for optimal signal quality.
Refer to the
NI Digital Waveform Generator/Analyzer Help
for more information about signal
termination.
Figure 12.
Dynamic Generation Functional Diagram
Dynamic Acquisition
When performing dynamic acquisition with the NI 654
x
/655
x
, the source generating the signals
needs a matched source impedance as close to 50
Ω
as possible to minimize signal reflections
and maintain optimal signal quality. Figure 13 shows a diagram of a dynamic acquisition system
using the NI 655
x
as an example.
Figure 13.
Dynamic Acquisition Functional Diagram
NI 655
X
NI CB-2162
Peripher
a
l
Device
50 C
ab
le
50
NI 655
X
NI CB-2162
R
S
R
T
Peripher
a
l
Device
50 C
ab
le
