Diode PN

Source

/dico/elec/diode.jpg

Description

  • Non-linear semiconductor PN junction.

  • It is free-controlled.

  • The model is the same as in Spice simulators (see [Spice1994]).

  • It is made of the serial connection of

    1. a resistor $R$ with

    2. the parallel connection of

      1. a minimal conductance and
      2. a nonlinear branch that restores the Shockley diode law.

  • The constitutive law is [Shockley1949] $$ \left\{ \begin{array}{rcl} w(t) & = & i(t), \\ v(t) & = & z(w(t)) = \mu\,v_0 \, \log\left(\frac{w(t)}{I_s}+1\right), \end{array}\right. $$ or $$ \left\{ \begin{array}{rcl} w(t) & = & v(t), \\ i(t) & = & z(w(t)) = I_s\,(\exp\left(\frac{w(t)}{\mu\,v_0}\right)-1), \end{array}\right. $$

  • The minimal conductance is a configuration parameter of the module pyphs.dictionary.

Parameter Description (SI unit) Typical value
$I_s$ saturation current (A) 2e-9
$v_0$ thermal voltage (V) 26e-3
$\mu$ ideality factor (d.u) 1.7
$R$ connectors resistance ($\Omega$) 0.5

Usage

electronics.diodepn label ('N1', 'N2'): Is=('Issymb', Isval), v0=('v0symb', v0val), mu=('musymb', muval);
label:
string, diode label.
N1, N2:
strings, nodes labels. Positive direction of current is "N1 -> N2".
Issymb:
string, saturation current parameter symbol.
Isval:
strictly positive float, saturation current parameter value.
v0symb:
string, thermal voltage parameter symbol.
v0val:
strictly positive float, thermal voltage parameter value.
musymb:
string, ideality factor parameter symbol.
muval:
strictly positive float, ideality factor parameter value.
Rsymb:
string, connectors resistance parameter symbol.
Rval:
strictly positive float, connectors resistance parameter value.

Example

For a diode named D1 between nodes A and B, with typical parameters values:

  • In netlist.net
electronics.diodepn D1 ('A', 'B'): Is=('Is', 2e-9), v0=('v0', 26e-3), mu=('mu', 1.7), R=('Rd1', 0.5);
  • In script.py
# diode
diode = {'dictionary': 'electronics',
         'component': 'diodepn',
         'label': 'D1',
         'nodes': ('OUT', datum),
         'arguments': {'Is': ('Is', 2e-9),
                       'v0': ('v0', 26e-3),
                       'R': ('Rd1', 0.5),
                       'mu': ('mu', 1.7)}}
phs.graph.netlist.add_line(diode)

References

[Shockley1949] Shockley, W. (1949). The Theory of p-n Junctions in Semiconductors and p-n Junction Transistors. The Bell System Technical Journal. 28 (3): 435–489. Equation 3.13 on page 454.
[Spice1994] Vladimirescu, A. (1994). The SPICE book. John Wiley & Sons, Inc..

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