Extra Element Theorem - Driving Point Impedances

Driving Point Impedances

As a special case, the EET can be used to find the input impedance of a network. For this application the EET can be written as:

Z_{in} = Z^{\infty}_{in} \left( \frac{1+\frac{Z^0_{e}}{Z}}{1+\frac{Z^{\infty}_{e}}{Z}} \right)

where

is the impedance chosen as the extra element
is the input impedance with Z removed (or made infinite)
is the impedance seen by the extra element Z with the input shorted (or made zero)
is the impedance seen by the extra element Z with the input open (or made infinite)

Computing these three terms may seem like extra effort, but they are often easier to compute than the overall input impedance.

Read more about this topic:  Extra Element Theorem

Famous quotes containing the words driving and/or point:

    “Death is another milestone on their way.
    With laughter on their lips and with winds blowing round them
    They record simply
    How this one excelled all others in making driving belts.”
    —Stephen Spender (1909–1995)

    “From the point of view of the pharmaceutical industry, the AIDS problem has already been solved. After all, we already have a drug which can be sold at the incredible price of $8,000 an annual dose, and which has the added virtue of not diminishing the market by actually curing anyone.”
    —Barbara Ehrenreich (b. 1941)