National Instruments NI PXI-4220, Руководство пользователя

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Glossary
© National Instruments Corporation G-3 NI PXI-4220 User Manual
CH channel—pin or wire lead to which you apply or from which you read the
analog or digital signal. Analog signals can be single-ended or differential.
For digital signals, you group channels to form ports. Ports usually consist
of either four or eight digital channels.
channel clock the clock controlling the time interval between individual channel sampling
within a scan. Devices with SS/H do not have this clock.
channel rate reciprocal of the interchannel delay
CMR common-mode rejection
CMRR common-mode rejection ratio—the ability of an instrument to reject
interference from a common-mode signal, usually expressed in
decibels (dB)
common-mode signal any voltage present at the instrumentation amplifier inputs with respect to
amplifier ground
counter/timer a circuit that counts external pulses or clock pulses (timing)
CTR counter
D
D/A digital-to-analog
DAC digital-to-analog converter—an electronic device, often an integrated
circuit, that converts a digital number into a corresponding analog voltage
or current
DAQ data acquisition—(1) collecting and measuring electrical signals from
sensors, transducers, and test probes or fixtures and inputting them to a
computer for processing; (2) collecting and measuring the same kinds of
electrical signals with A/D and/or DIO devices plugged into a computer,
and possibly generating control signals with D/A and/or DIO devices in the
same computer
DAQ Assistant
a configuration utility with which you define and configure your DAQ
operation
DAQ-STC data acquisition system timing controller chip