Glossary
©NationalInstruments Corporation G-7 NI5620 User Manual
random interleaved
sampling
method ofincreasing sample rate by repetitively sampling a repeated
waveform
real-time sampling sampling that occurs immediately
record length thesize of a chunk (or record) of data that can be or has been acquired by a
device
resolution the smallest signal increment that can be detected bya measurement
system.Resolution can be expressed in bits, in proportions, or in percent
offull scale. For example, a system has 12-bit resolution, one part in
4,096 resolution, and 0.0244% of full scale.
rms rootmean square—a measure of signal amplit ude; the square root of the
averagevalue of the square of the instantaneous signal amplitude
ROM read-only memory
Ss seconds
S samples
S/s samplesper second—used to express the rate at which an instrument
samples an analog signal
sample rate the speed that a devicecan acquire data
sense in four-wire resistance the sense measures the voltage across the resistor
being excitedby the excitation current
settling time the amount of time required for a voltageto reach its final value within
specifiedlimits
Shannon Sampling
Theorem
atheorem stating that a signal must be sampled at least twice as fast as the
bandwidth oft hesignal to accurately reconstruct the signal as a waveform
sourcei mpedance aparameter 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)
systemnoise a measure of the amount of noise seen byan analog circuit or an ADC when
the analog inputs are grounded