Glossary
AT-MIO-16X User Manual G-22
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National Instruments Corporation
SE single-ended—a term used to describe an analog input that is measured
with respect to a common ground
self-calibrating a property of a DAQ board that has an extremely stable onboard
reference and calibrates its own A/D and D/A circuits w ithout m anua l
adjustments by the user
sensor a device that responds to a physical stimulus (heat, light, sound,
pressure, motion, flow, and so on), and produces a corresponding
electrical signal
settling time the amount of time required for a voltage to reach its final value within
specified limits
S/H sample-and-hold—a circuit that ac quires and store s an analog voltag e
on a capacitor for a short period of time
shared memory See dual-access memory
signal conditioning the manipulation of signals to prepare them for digitizing
signal divider performing fre quen cy div ision o n an e xterna l signa l
SIMM single in-line memory module
SMB a type of miniature coaxial signal connector
SNR signal-to-noise ratio—the ratio of the overall rms signal level to the rms
noise level, expressed in dB
software trigger a programmed event that triggers an event such as data acquisition
software triggering a method of trig gering in which yo u s imula te an ana log trigger using
software. Also called conditional retrieval.
source impedance a parameter of signal sources that reflects current-driving ability of
voltage sources (lower is better) and the voltage-driving ability of
current sources (higher is better)
SOURCE input pin an counter input pin where the counter counts the signal transitions
SPDT single-pole dou ble throw—a property of a switch in which one terminal
can be connected to one of two other terminals
SS simultaneous sampling—a property of a system in which each input or
output channel is digitized or updated at the same instant