Simulation of an diode using the built in parameters

Schematic Simulation (Ngspice)
1

I would like to understand the built in parameters for the diode in Spice simulation.

There are many to choose from and I was hoping someone could help me with a quick explanation. I suspect most of them can be left untouched for a ballpark simulation.

What are the settings if I want to simulate:

  1. A standard diode (with a forward voltage drop of 0.7V)
  2. An ideal diode (no voltage drop or resistance)
  3. A rectified mosfet (with Rds_on of 2mOhm)

many thanks!
/Jonas

2

The parameters of all those basic models are described in the ngSpice manual. In general, a model specification for a diode is just a single line of text with those parameters, and they’re easy to modify.

3

Just search 1N4148 or 1N4007 (depending what you understand as standard) diode model at their manufacturers websites.

4
  1. Use standard settings of diode in library Simulation_SPICE.
  2. change dc parameters: n from 1 to 0.001 and rs to small value (zero may or may not generate convergence issues).
  3. NMOS device from Simulation_SPICE with VDMOS model: change kp, rd and rb.
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5

Thank you all! Appreciated

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