Glossary
©
National Instruments Corporation
G-7
SCXI-1502 User Manual
N
NC
Normally closed, or not connected.
NI-DAQ
The driver software needed in order to use E/M Series DAQ devices and
SCXI components.
noise
An undesirable electrical signal—noise comes from external sources such
as AC power lines, motors, generators, electrical storms, welders, radio
transmitters, and internal sources such as semiconductors, resistors, and
capacitors. Noise corrupts signals you are trying to measure.
nonlinearity
For an amplifier, a measure of the maximum output deviation from an ideal
linear response in units of percent relative to full scale. The ideal linear
response is taken to be a straight line on a plot of measured output voltage
to measured input voltage with the ends of the line connecting the extremes
of the plot at the full-scale limits.
O
OUT
Output signal.
OUT REF
Output reference signal.
overvoltage protection
Maximum voltage that does not cause hardware damage.
P
passband
The range of input frequencies that are passed to the filter output without
attenuation.
pole
A term used to describe the quality of a lowpass filter. In general, the more
poles a lowpass filter has, the better it attenuates frequencies beyond the
cutoff frequency.
ppm
Parts per million.
PXI
PCI eXtensions for Instrumentation–an open specification that builds on
the CompactPCI specification by adding instrumentation-specific features.
