Glossary
©
National Instruments Corporation
G-3
D
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 boards plugged into a computer, and
possibly generating control signals with D/A and/or DIO boards in the
same computer
DAQ device
a data acquisition device. Examples are DIO, E series MIO, and Lab/1200
plug-in data acquisition devices.
dB
decibel—the unit for expressing a logarithmic measure of the ratio of two
signal levels: dB = 20 log
10
(V1/V2), for signals in volts
DC
direct current
DC coupled
allowing the transmission of both AC and DC signals
differential input
the two-terminal input to a differential amplifier
DIGGND
digital ground signal
DIN
Deutsche Industrie Norme
DIO
digital I/O
DMM
digital multimeter
droop rate
the rate that a sample-and-hold circuit in hold mode deviates from the true
hold value, expressed in millivolts per second
dynamic impedance
the ratio of voltage change of a system over its current change, expressed
in ohms
E
EEPROM
electrically erasable programmable read-only memory—ROM that can be
erased with an electrical signal and reprogrammed. Some SCXI modules
contain an EEPROM to store measurement-correction coefficients.
EMC
electromechanical compliance
EMI
electromagnetic interference
excitation
supplying a voltage or current source to energize an active sensor or circuit