Input Polarity And Input Range; Digital Trigger; Using Test Panels To Acquire A Signal - National Instruments NI 4472 User Manual

Input Polarity and Input Range

Caution Connections that exceed the rated input voltages can damage the computer and
the connected equipment. Overvoltage protection is ±42.2 V on the positive signal line.
The shield does not have overvoltage protection. Do not make a non-ground connection to
the shield. Also, do not connect the shield to a ground that varies more than ±2.5 V from
the ground of the NI 4472. National Instruments is not liable for any damages resulting
from such connections.

Digital Trigger

Using Test Panels to Acquire a Signal

© National Instruments Corporation
The NI 4472 analog inputs are bipolar, that is, the input voltage range is
centered on 0 V. The input voltage range is ±10 V with 1.19 µV resolution,
and is always at a gain of 1.0 (0 dB). Due to the large dynamic range of
the ADC used on the NI 4472, programmable gain is not required for most
applications. Since the NI 4472 does not have hardware to adjust the input
gain, the component count in the input signal path is reduced, resulting in
a cleaner signal. If the input signal has an amplitude greater than ±10 V,
it will be clipped and introduce large errors that can be easily identified
in the frequency spectrum.
All data read from the ADC is interpreted as two's complement format.
In two's complement mode, digital data values read from the analog input
channel are either positive or negative.
You can use the EXT TRIG SMB connector on the NI 4472 for external
digital triggering.
To quickly test your signal connections and the operation of your system,
you can use the Test Panels to view a signal input to your NI 4472. To do
so, follow these instructions:
1. Connect a known signal to an analog input channel on the NI 4472.
2. Launch Measurement & Automation Explorer (MAX) from the
desktop.
3. Open the Devices and Interfaces folder.
4. Right-click the icon for the NI 4472 device you want to test and select
Test Panel from the pop-up menu.
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Chapter 2 Using Your NI 4472
NI 4472 User Manual