Glossary
NI 6124/6154 User Manual G-10 ni.com
tgw Gate pulse width.
THD Total harmonic distortion—the ratio of the total rms signal due to harmonic
distortion to the overall rms signal, in dB or percent.
THD+N Signal-to-THD plus noise—the ratio in decibels of the overall rms signal to
the rms signal of harmonic distortion, plus noise introduced.
thermocouple A temperature sensor created by joining two dissimilar metals. The
junction produces a small voltage as a function of the temperature.
toff An offset (delayed) pulse; the offset is t nanoseconds from the falling edge
of the AI CONV CLK* signal.
tout Output delay time.
tpPeriod of a pulse train.
transducer See sensor.
tsc Source clock period.
tsp Source pulse width.
TTL Transistor-transistor logic—a digital circuit composed o f bipolar
transistors wired in a certain manner. A typical medium-speed digital
technology. Nominal TTL logic levels are 0 and 5 V.
VV Volts.
VCC Nominal +5 V power supply provided by the PC motherboard.
Vcm Common-mode noise and ground potential.
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.
VIH Volts, input high.