Owner's manual

Glossary
76
IMD Intermodulation Distortion: The ratio, in
dB, of the total rms signal level of
harmonic sum and difference distortion
products, to the overall rms signal level.
The test signal is two sine waves added
together according to the following
standards:
Input Impedance The measured 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.
Integral Control A control action that eliminates the
offset inherent in proportional control.
Interpreter A software utility that executes source
code from a high-level language such
as Basic, C or Pascal, by reading one
line at a time and executing the
specified operation. See also Compiler.
Interrupt A computer signal indicating that the
CPU should suspend its current task to
service a designated activity.
I/O Input/Output: The transfer of data
to/from a computer system involving
communications channels, operator
interface devices, and/or data
acquisition and control interfaces.
IPC Interprocess Communication Protocol
by which processes can pass messages.
Messages can be either blocks of data
and information packets, or instructions
and requests for pro-cess(es) to
perform actions. A process can send
messages to itself, other processes on
the same machine, or processes located
anywhere on the network.
Isolation Voltage The voltage that an isolated circuit can
normally withstand, usually specified
from input to input and/or from any