Chapter 1
Generating Functions with the NI 5401
1-4
ni.com
ARB Connector
The ARB (PCI) or ARB OUT (PXI) connector provides the waveform
output. The maximum output levels on this connector depend on the type
of load termination. If the output of your NI 5401 terminates into a
50
Ω
load, the output levels are ±5 V, as shown in Figure 1-2. If the output
of your NI 5401 terminates into a high-impedance load (HiZ), the output
levels are ±10 V. If the output terminates into any other load, the levels are
as follows:
where V
out
is the maximum output voltage level
R
L
is the load impedance in ohms, and
R
O
is the output impedance on the NI 5401.
By default,
R
O
= 50
Ω
, but you can use your software to set it to 75
Ω
.
Figure 1-2.
Output Levels and Load Termination Using a 50
Ω
Output Impedance
Note
Software sets the voltage output levels based on a 50
Ω
load termination.
For more information on waveform generation and analog output
operation, refer to Chapter 2,
. For
specifications on the waveform output signal, see Appendix A,
SYNC Connector
The SYNC (PXI) or SYNC OUT (PXI) connector provides a TTL version
of the sine waveform being generated at the output. You can think of the
SYNC output as a very high-frequency resolution, software-programmable
clock source for many applications. You can also dynamically vary the
V
out
R
L
R
L
R
O
+
-------------------
10
×
V
±
=
ARB
NI 5401
Load
±5 V
R
L
=
50
Ω
50
Ω
Load
R
O
=
50
Ω
ARB
NI 5401
Load
±10 V
R
L
=
HiZ
High-Impedance Load
R
O
=
50
Ω