National Instruments PCI-6110E/6111E - Manual (Page 103)

Glossary
PCI-6110E/6111E User Manual G-10 © National Instruments Corporation
THD total harmonic distortion—the ratio of the total rms signal due to
harmonic distortion to the overall rms signal, in decibel or a
percentage
thermocouple a temperature sensor created by joining two dissimilar metals. The
junction produces a small voltage as a function of the temperature.
TRIG trigger signal
t
sc
source clock period
t
sp
source pulse width
TTL transistor-transistor logic
U
UI update interval
UISOURCE update interval counter clock signal
unipolar a signal range that is always positive (for example, 0 to +10 V)
UPDATE update signal
V
V volts
VDC volts direct current
VI virtual instrument—(1) a combination of hardware and/or software
elements, typically used with a PC, that has the functionality of a
classic stand-alone instrument (2) a LabVIEW software module
(VI), which consists of a front panel user interface and a block
diagram program
V
IH
volts, input high
V
IL
volts, input low
V
in
volts in
V
m
measured voltage
PCI_E.book Page 10 Thursday, June 25, 1998 12:55 PM