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If you are creating your own accessory to use with your 

device, you can purchase the mating connector for the VHDCI 
cable from NI (part number 778914-01).

Whether you use NI cables and accessories or design your own, you should 
properly terminate cables to avoid improper measurements due to signal 
reflections, overshoot, and undershoot. Refer to the NI Digital Waveform 
Generator/Analyzer Help for more information about signal termination.

Dynamic generation and dynamic acquisition are two categories of 
applications that you can create for NI digital waveform generator/analyzers. 
This section provides information on the general wiring considerations for 
each type of application. Both examples use the NI CB-2162 for signal 
termination.

When performing dynamic generation, an NI digital waveform 
generator/analyzer 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 6 shows a diagram of such a system, using the NI 655X 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 6.  Dynamic Generation Functional Diagram

NI 655

X

NI CB-2162

Peripheral
Device

50     Cable

50