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National Instruments AT-MIO-16X User Manual

Page 307

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Glossary

AT-MIO-16X User Manual

G-24

© National Instruments Corporation

thermistor

a semiconductor sensor that exhibits a repeatable change in electrical
resistance as a function of temperature. Most thermistors exhibit a
negative temperature coefficient.

thermocouple

a temperature sensor created by joining two dissimilar metals. The
junction produces a small voltage as a function of the temperature.

throughput rate

the data, measured in bytes/s, for a given continuous operation,
calculated to include software overhead. Throughput Rate = Transfer
Rate Software Overhead Factor.

top-level VI

VI at the top of the VI hierarchy. This term is used to distinguish the VI
from its subVIs.

transducer

See sensor

transducer excitation

a type of signal conditioning that uses external voltages and currents to
excite the circuitry of a signal conditioning system into measuring
physical phenomena

transfer rate

the rate, measured in bytes/s, at which data is moved from source to
destination after software initialization and set up operations; the
maximum rate at which the hardware can operate

trigger

any event that causes or starts some form of data capture

TTL

transistor-transistor logic

U

UART

universal asynchronous receiver/transmitter—an integrated circuit that
converts parallel data to serial data (and vice versa), commonly used as
a computer bus to serial device interface for serial communication

UI

update interval

unipolar

a signal range that is always positive (for example, 0 to +10 V)

update

the output equivalent of a scan. One or more analog or digital output
samples. Typically, the number of output samples in an update is equal
to the number of channels in the output group. For example, one pulse
from the update clock produces one update which sends one new sample
to every analog output channel in the group.