National Instruments PXI NI 5401 User Manual
Page 50
Glossary
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National Instruments Corporation
G-3
DC
direct current
DC coupled
allowing the transmission of both AC and DC signals
DDS
direct digital synthesis—a digital technique of frequency generation using
a numerically controlled oscillator (NCO), a dedicated lookup memory,
and a DAC
DDS mode
a method of waveform generation that uses built-in DDS functionality to
generate very high frequency resolution standard waveforms
DGND
digital ground signal
digital word
See word.
driver
software that controls a specific hardware device
dynamic range
the ratio of the largest signal level a circuit can handle to the smallest signal
level it can handle (usually taken to be the noise level), normally expressed
in dB
E
EEPROM
electrically erasable programmable read-only memory—ROM that can be
erased with an electrical signal and reprogrammed
external trigger
a voltage pulse from an external source that triggers an event such as A/D
conversion
EXT_TRIG
external trigger input signal