National Instruments NI 5911 User Manual
Page 36
Glossary
© National Instruments Corporation
G-3
clock
hardware component that controls timing for reading from or writing to
groups
CMRR
common-mode rejection ratio—a measure of an instrument’s ability to
reject interference from a common-mode signal, usually expressed in
decibels (dB)
counter/timer
a circuit that counts external pulses or clock pulses (timing)
coupling
the manner in which a signal is connected from one location to another
D
dB
decibel—the unit for expressing a logarithmic measure of the ratio of
two signal levels: dB=20log10 V1/V2, for signals in volts
DC
direct current
default setting
a default parameter value recorded in the driver. In many cases, the default
input of a control is a certain value (often 0) that means use the current
default setting.
device
a plug-in data acquisition board, card, or pad. The NI 5911 is an example
of a device.
differential input
an analog input consisting of two terminals, both of which are isolated from
computer ground, whose difference is measured
double insulated
a device that contains the necessary insulating structures to provide electric
shock protection without the requirement of a safety ground connection
drivers
software that controls a specific hardware instrument
E
EEPROM
electrically erasable programmable read-only memory—ROM that can be
erased with an electrical signal and reprogrammed
equivalent time
sampling
any method used to sample signals in such a way that the apparent sampling
rate is higher than the real sampling rate
event
the condition or state of an analog or digital signal