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Glossary Multifunction Reconfigur able I/O User Manual G-4 © National Instruments Corporation E EEPR OM Electrically erasable programmabl e read-only memory—R OM that can be erased with an electrical signal and reprogram…
Glossary
© National Instruments Corporation G-3 Multifunction Reconfigurable I/O User Manual
CMOS Complementary metal-oxide semiconductor.
CMRR Common-mode rejection ratio—A measure of an instrument’s ability to
reject interference from a common-mode signal, usually expressed in
decibels (dB).
common-mode
voltage
Any voltage present at the instrumentation amplifier inputs with respect to
amplifier ground.
CompactPCI Refers to the core specification defined by the PCI Industrial Computer
Manufacturer’s Group (PICMG).
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—A system that uses the computer to collect, receive,
and generate electrical signals.
dB Decibel—The unit for expressing a logarithmic measure of the ratio of
two signal levels: dB = 20log10 V1/V2, for signals in volts.
DC Direct current.
DGND Digital ground signal.
DIFF Differential mode.
DIO Digital input/output.
DIO<i> Digital input/output channel signal.
DMA Direct memory access—A method by which data can be transferred
to/from computer memory from/to a device or memory on the bus while the
processor does something else. DMA is the fastest method of transferring
data to/from computer memory.
DNL Differential nonlinearity—A measure in LSB of the worst-case deviation of
code widths from their ideal value of 1 LSB.
DO Digital output.
Glossary
Multifunction Reconfigurable I/O User Manual G-4 © National Instruments Corporation
E
EEPROM Electrically erasable programmable read-only memory—ROM that can be
erased with an electrical signal and reprogrammed.
F
FPGA Field-Programmable Gate Array.
FPGA VI A configuration that is downloaded to the FPGA and that determines the
functionality of the hardware.
G
glitch An unwanted signal excursion of short duration that is usually unavoidable.
H
hHour.
HIL Hardware-in-the-loop.
Hz Hertz.
I
I/O Input/output—The transfer of data to/from a computer system involving
communications channels, operator interface devices, and/or data
acquisition and control interfaces.
INL Relative accuracy.
L
LabVIEW Laboratory Virtual Instrument Engineering Workbench. LabVIEW is a
graphical programming language that uses icons instead of lines of text to
create programs.
LSB Least significant bit.
Glossary
© National Instruments Corporation G-5 Multifunction Reconfigurable I/O User Manual
M
m Meter.
max Maximum.
min Minimum.
MIO Multifunction I/O.
monotonicity A characteristic of a DAC in which the analog output always increases as
the values of the digital code input to it increase.
mux Multiplexer—A switching device with multiple inputs that sequentially
connects each of its inputs to its output, typically at high speeds, in order to
measure several signals with a single analog input channel.
N
noise An undesirable electrical signal—Noise comes from external sources such
as the AC power line, motors, generators, transformers, fluorescent lights,
CRT displays, computers, electrical storms, welders, radio transmitters,
and internal sources such as semiconductors, resistors, and capacitors.
Noise corrupts signals you are trying to send or receive.
NRSE Nonreferenced single-ended mode—All measurements are made with
respect to a common (NRSE) measurement system reference, but the
voltage at this reference can vary with respect to the measurement system
ground.
O
OUT Output pin—A counter output pin where the counter can generate various
TTL pulse waveforms.