Chapter 2
Function Generator Operation
©
National Instruments Corporation
2-15
♦
NI 5401 for PXI
For frequency locking to other boards, the NI 5401 for PXI receives the
PXI backplane 10 MHz Osc as a reference clock signal. All the NI 5401s
for PXI use this common signal as the reference clock for frequency
locking.
Note
Refer to your software documentation for selecting and routing signals to the
RTSI/PXI trigger bus.
Calibration
Calibration is the process of minimizing measurement errors by making
small circuit adjustments. On the NI 5401, NI-FGEN automatically makes
these adjustments by retrieving predetermined constants from the onboard
EEPROM, calculating correction values, and writing those values to the
CalDACs.
National Instruments calibrates all NI 5401 devices to the levels indicated
in Appendix A,
. Factory calibration involves procedures
such as nulling the offset and gain errors. However, since offset and gain
errors may drift with time and temperature, you may need to recalibrate
your device. The NI 54
XX
Calibration Toolkit provides functionality which
allows you to perform a full recalibration of your device and allows the
device to perform a self-calibration. The toolkit, including documentation,
is included with NI-FGEN and is also available online at
ni.com/support/calibrat
. Contact National Instruments for more
information.