Search results
Results from the WOW.Com Content Network
For a circuit to be modelled with an ideal source, output impedance, and input impedance; the circuit's input reactance can be sized to be the negative of the output reactance at the source. In this scenario, the reactive component of the input impedance cancels the reactive component of the output impedance at the source.
In electrical engineering, impedance is the opposition to alternating current presented by the combined effect of resistance and reactance in a circuit. [1]Quantitatively, the impedance of a two-terminal circuit element is the ratio of the complex representation of the sinusoidal voltage between its terminals, to the complex representation of the current flowing through it. [2]
The input impedance of an infinite line is equal to the characteristic impedance since the transmitted wave is never reflected back from the end. Equivalently: The characteristic impedance of a line is that impedance which, when terminating an arbitrary length of line at its output, produces an input impedance of equal value. This is so because ...
Impedance matching, the adjustment of input impedance and output impedance; Mechanical impedance, a measure of opposition to motion of a structure subjected to a force; Wave impedance, a constant related to electromagnetic wave propagation in a medium Impedance of free space, a universal constant and the simplest case of a wave impedance
In electrical engineering, impedance matching is the practice of designing or adjusting the input impedance or output impedance of an electrical device for a desired value. Often, the desired value is selected to maximize power transfer or minimize signal reflection .
The input impedance is the current gain (β) divided by the transconductance. The output (collector) conductance is determined by the Early voltage and is proportional to the collector current. For most transistors in linear operation it is well below 100 μS .
In addition to the basic instrument, most oscilloscopes are supplied with a probe. The probe connects to any input on the instrument and typically has a resistor of ten times the oscilloscope's input impedance. This results in a 0.1 (‑10×) attenuation factor; this helps to isolate the capacitive load presented by the probe cable from the ...
The VTVM had a fixed input impedance of typically 1 MΩ or more, usually through use of a cathode follower input circuit, and thus did not significantly load the circuit being tested. VTVMs were used before the introduction of electronic high-impedance analog transistor and field effect transistor voltmeters (FETVOMs). Modern digital meters ...