Diode modelling

In <a href="/facts/Electronics/E4JhgISq">electronics</a>, diode modelling refers to the mathematical models used to approximate the actual behaviour of real diodes to enable calculations and circuit analysis. A <a href="/facts/Diode/JyaoyGnk">diode</a>'s <a href="/facts/Electrical_current/Dc1xdnUX">I</a>-<a href="/facts/Voltage/EN2po6N2">V</a> curve is <a href="/facts/Nonlinear/4aYItALC">nonlinear</a>.
A very accurate, but complicated, physical model composes the I-V curve from three <a href="/facts/Exponential_function/ewlYxvR2">exponentials</a> with a slightly different steepness (i.e. <a href="/facts/Ideality_factor/3wx4F0Aw">ideality factor</a>), which correspond to different <a href="/facts/Carrier_generation_and_recombination/2UtL6mJp">recombination</a> mechanisms in the device; at very large and very tiny currents the curve can be continued by linear segments (i.e. resistive behaviour).
In a relatively good approximation a diode is modelled by the single-exponential <a href="/facts/Shockley_diode_equation/6sE305zS">Shockley diode law</a>. This nonlinearity still complicates calculations in circuits involving diodes 
so even simpler models are often used.
This article discusses the modelling of <a href="/facts/P-n_junction/CaKIdLPg">p-n junction</a> diodes, but the techniques may be generalized to other <a href="/facts/Solid_state_(electronics)/US0Qbq28">solid state</a> diodes.

Diode modelling open-in-new

Diode modelling