Chapter3 HardwareOverview
ATE Series User Manual 3-14 ni.com
Selectinga bipol arrange for aparticular DAC means that any data written
to thatDAC is interpreted as two’s complement format. In two’s
complementmode, data valueswritten to the AO channel can be either
positiveor negative. If you select unipolar range, data is interpreted in
straightbinary format. In straight binary mode, data values written to the
AOchannel range must be positive.
♦AT-MIO-16XE-10
Youcan configure each AO channel for either unipolar or bipolar output.
A unipolar configuration has ar ange of 0 to 10 V at the analog output.
A bipolar configurationhas a range of –10 to +10 V at the analog output.
Youdo not need to configure both channels for the same range.
Analog Output Reglitch Selection
♦AT-MIO-16E-1,AT-MIO-16E-2, and AT-MIO-64E-3only
In normal operation, a DACoutput glitches whenever it is updated with
an ewvalue. The glitch energy differs from code to code and appears
asdistortion in the frequency spectrum. Each analog output of the
AT-MIO-16E-1,AT-MIO-16E-2, and AT-MIO-64E-3contains a reglitch
circuitthat generates uniform glitch energy at every code rather than large
glitches at the major code transitions. This uniform glitch energy appears
asa multi ple of the update rate in the frequency spectrum. Notice that this
reglitchcircuit does not eliminate the glitches; it only makes them more
uniform in size. Reglitching is normally disabled at startup and can be
independently enabled for each channel through software.
Analog Trigger♦AT-MIO-16E-1,AT-MIO-16E-2,AT-MIO-64E-3, AT-MIO-16XE-10,and
AT-AI-16XE-10only
In addition to supporting internal software triggering and external digital
triggering to initiate a data acquisition sequence, the AT-MIO-16E-1,
AT-MIO-16E-2,AT-MIO-64E-3,AT-MIO-16XE-10, and AT-AI-16XE-10
also support analog triggering. Youcan configure the analog trigger
circuitry toaccept either a direct analog input from the PFI0/TRIG1 pin
on the I/O connector or a postgain signal from the output of the PGIA, as
shownin Figure 3-8. The trigger-level range for the direct analog channel
is ±10 V in 78 mV steps for the AT-MIO-16E-1,AT-MIO-16E-2, and
AT-MIO-64E-3,and ±10 V in 4.9 mV steps for the AT-MIO-16XE-10and
AT-AI-16XE-10.The range for the post-PGIA trigger selection is simply