The value of an ideal voltage source in conjunction with a fictional resistor that would supply the same amount of AC voltage across a power supply's terminal that the magnitude and frequency of alternating current would supply.
The source impedance an amplifier presents to a loudspeaker. The lower the source impedance the greater difficulty a loudspeaker will have in feeding Back EMF to the driving amplifier, and the greater the level of control the amplifier will be able to exert over the loudspeaker.
A specification that allows calculation of the change in output amplitude with changing load impedance (MIL-PRF-55310D, 4.8.26).
The impedance seen by an electrical load attached to the output terminals of an audio or video device. For practical purposes, the output impedance of any audio amplifying equipment should be low in comparison to what it is connected to. It should not only be low at low frequencies, where it will affect bass damping, but should also be low at higher frequencies to insure a flat frequency response. In video systems, output and input impedances should closely match.
The impedance a device presents to its load. The impedance measured at the output terminals of a transducer with the load disconnected and all impressed driving forces taken as zero.
The opposition to current flow by the output circuits of an amplifier (or other device).
The resistance as measured on the output terminals of a pressure transducer.
The electrical impedance between the conductors of a device's output. It is the actual impedance at the output terminals.
Resistance to the flow of current at the output of an electronic device (see Impedance). TOP OF GLOSSARY
the impedance across the output terminals of a sensor presented by the sensor to the associated external circuitry.
Resistance across the output terminals of a device as 'seen' by the load.
The ratio of change in output voltage to change in load current.
An output resistance value of analog voltage (current) output. This describes the protective resistance of an output circuit. The value measured with the instrument is the voltage divided by the output's output impedance and the instrument's input impedance. Consequently, the smaller output impedance enables measurement of a value closer to the true value.
A measure of resistance to alternating current. Sound sources with low output impedance (ie below 100 ohms) can help to ensure that they will be compatible with most amplifiers, even with long interconnect cables.
The output impedance, source impedance, or internal impedance of an electronic device is the opposition exhibited by its output terminals to the flow of an alternating current (AC) of a particular frequency as a result of resistance, inductance and capacitance.