National Instruments PCI-6238, Руководство пользователя

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Glossary
NI 6238/6239 User Manual G-4 ni.com
cascading Process of extending the counting range of a counter chip by connecting to
the next higher counter.
CE European emissions control standard.
channel Pin or wire lead to which you apply or from which you read the analog or
digital signal. For digital signals, you group channels to form ports. Ports
usually consist of either four or eight digital channels.
clock Hardware component that controls timing for reading from or writing to
groups.
CMOS Complementary metal-oxide semiconductor.
CMRR Common-mode rejection ratio—A measure of the ability of a differential
amplifier to reject interference from a common-mode signal, usually
expressed in decibels (dB).
common-mode rejection The ability of an electronic system to cancel any electronic noise pick-up
that is common to both the positive and negative polarities of the input leads
to the instrument front end. Common mode rejection is only a relevant
specification for systems having a balanced or differential input.
common-mode signal 1. Any voltage present at the instrumentation amplifier inputs with
respect to amplifier ground.
2. The signal, relative to the instrument chassis or computer’s ground, of
the signals from a differential input. This is often a noise signal, such
as 50 or 60 Hz hum.
connector 1. A device that provides electrical connection.
2. A fixture (either male or female) attached to a cable or chassis for
quickly making and breaking one or more circuits. A symbol that
connects points on a flowchart.
convert rate Reciprocal of the interchannel delay.
count The number of events, such as zero crossings, pulses, or cycles.