NI CB-2162 User Guide
12
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Terminating Signals
Termination of high-speed digital signals is necessary to prevent signal
reflections and to force signal channels to a known state when no signal
is present. Sockets for terminating resistors are connected to all DIO and
control channels on the NI CB-2162. These sockets are labeled in Figure 1.
Note
Proper termination needs are application-specific. For some special considerations
for choosing resistor values, refer to the
Terminating Control Channel Signals
section.
Minimizing the Effects of Stubs
Stubs are unterminated tributaries from the original signal path. Stubs
decrease the signal quality of the system by adding reflections to the
transmission channels. To minimize the effect of stubs, termination is
placed at the end of the signal path.
If your signal transmission line ends on the NI CB-2162, you can use the
provided termination socket. If your signal terminates somewhere other
than the NI CB-2162, NI recommends terminating the transmission line
at the final signal destination.
Note
Refer to the help file for your device for more information about proper signal
termination.
Terminating DIO Channel Signals
Table 2 shows the relationship between DIO channels and the termination
sockets.
Note
Refer to the help file for your device for information about the number of available
DIO channels on your device. DIO <20..31> may not be applicable to your device.
You can use different resistor networks and jumper placements to terminate
the DIO channels in multiple configurations.
Table 2.
DIO Termination Sockets
DIO Channels
Termination Socket
DIO <0..7>
J13
DIO <8..15>
J15
DIO <16..23>
J17
DIO <24..31>
J19
