National Instruments NI 783 R Series, User Manual

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Glossary
© National Instruments Corporation G-3 R Series Multifunction RIO User Manual
CMOS Complementary metal-oxide semicond
u
ctor.
CMRR Common-mode rejection ratio—A meas
u
re of an instr
u
ment’s ability to
reject interference from a common-mode signal,
u
s
u
ally expressed in
decibels (dB).
common-mode
voltage Any voltage present at the instr
u
mentation amplifier inp
u
ts with respect to
amplifier gro
u
nd.
CompactPCI Refers to the core specification defined by the PCI Ind
u
strial Comp
u
ter
Man
u
fact
u
rer’s Gro
u
p (PICMG).
D
D/A Digital-to-analog.
DAC Digital-to-analog converter—An electronic device, often an integrated
circ
u
it, that converts a digital n
u
mber into a corresponding analog voltage
or c
u
rrent.
DAQ Data acq
u
isition—A system that
u
ses the comp
u
ter to collect, receive,
and generate electrical signals.
dB Decibel—The
u
nit for expressing a logarithmic meas
u
re of the ratio of
two signal levels: dB = 20log10 V1/V2, for signals in volts.
DC Direct c
u
rrent.
DGND Digital gro
u
nd signal.
DIFF Differential mode.
DIO Digital inp
u
t/o
u
tp
u
t.
DIO< i > Digital inp
u
t/o
u
tp
u
t channel signal.
DMA Direct memory access—A method by which data can be transferred
to/from comp
u
ter memory from/to a device or memory on the b
u
s while the
processor does something else. DMA is the fastest method of transferring
data to/from comp
u
ter memory.
DNL Differential nonlinearity—A meas
u
re in LSB of the worst-case deviation of
code widths from their ideal val
u
e of 1 LSB.
DO Digital o
u
tp
u
t.