Glossary
G-8
www.natinst.com
I
OL
current, output low
in.
inches
INL
integral nonlinearity—a measure in LSB of the worst-case deviation from
the ideal A/D or D/A transfer characteristic of the analog I/O circuitry
input bias current
the current that flows into the inputs of a circuit
input impedance
the resistance and capacitance between the input terminals of a circuit
input offset current
the difference in the input bias currents of the two inputs of an
instrumentation amplifier
instrument driver
a set of high-level software functions that controls a specific GPIB, VXI,
or RS-232 programmable instrument or a specific plug-in DAQ device.
Instrument drivers are available in several forms, ranging from a function
callable language to a virtual instrument (VI) in LabVIEW.
instrumentation
amplifier
a circuit whose output voltage with respect to ground is proportional to the
difference between the voltages at its two high impedance inputs
interrupt
a computer signal indicating that the CPU should suspend its current task
to service a designated activity
interrupt level
the relative priority at which a device can interrupt
interval scanning
scanning method where there is a longer interval between scans than there
is between individual channels comprising a scan
IRQ
interrupt request
K
k
kilo—the standard metric prefix for 1,000, or 10
3
, used with units of
measure such as volts, hertz, and meters
K
kilo—the prefix for 1,024, or 2
10
, used with B in quantifying data or
computer memory
kS
1,000 samples