User manual

Glossary

CH channel—pin or wire lead to which you apply or from which you read the

analog or digital signal. Analog signals can be single-ended or differential.

For digital signals, you group channels to form ports. Ports usually consist

of either four or eight digital channels.

channel clock the clock controlling the time interval between individual channel sampling

within a scan. Devices with simultaneous sampling do not have this clock.

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)

common-mode signal any voltage present at the instrumentation amplifier inputs with respect to

amplifier ground

CONVERT* convert signal

counter/timer a circuit that counts external pulses or clock pulses (timing)

crosstalk an unwanted signal on one channel due to an input on a different channel

CTR counter

D/A digital-to-analog

DAC digital-to-analog converter—an electronic device, often an integrated

circuit, that converts a digital number into a corresponding analog voltage

or current

DAC0OUT analog channel 0 output signal

DAC1OUT analog channel 1 output signal

DAQ data acquisition—(1) collecting and measuring electrical signals from

sensors, transducers, and test probes or fixtures and inputting them to a

computer for processing; (2) collecting and measuring the same kinds of

electrical signals with A/D and/or DIO devices plugged into a computer,

and possibly generating control signals with D/A and/or DIO devices in the

same computer

dB decibel—the unit for expressing a logarithmic measure of the ratio of

two signal levels: dB=20log10 V1/V2, for signals in volts

UM.book Page 3 Monday, May 14, 2001 10:32 AM