Stats

  • Locked Locked
  • Replies 8
  • Subscribers 125
  • Views 36587
  • Members are here 0
This discussion has been locked.
You can no longer post new replies to this discussion. If you have a question you can start a new discussion

How to make an ideal diode model for diode from analogLib?

BaaB

I am trying to make a model and use it for ideal diode from analogLib library. However, I don't know how to modify the built-in potential (or forward voltage) of the diode. I tried to add VJ variable and set it to a small value like 0.1V. However, from I-V characteristic of simulation, it doesn't seem to have any effect on forward voltage at all. The built-in potential from the simulation is about 650mV. 

Can anybody tell me how to do that? I want the diode is like ideal (zero forward voltage and infinite slope).

Here is the model file I used (diode.scs):

simulator lang=spice

.model schottky D (LEVEL = 3 IS=1p RS=0 BV=40.0 IBV=1p VJ=0.1 CJO=0 M=0.5 N=1 TT=0 )


Parents

  • The diode model is not intended to be used as an "ideal" diode, so I don't think that's you're best starting point.

    Note - this comes with a bit of caution; modelling "ideal" components is often not a good idea in circuit simulators because they're really not intended for that. For a start, an infinite slope could lead to convergence problems.

    You could implement it with a relay in spectre:

    subckt idealDiode (a c)
    // note, the on resistance shouldn't be below 1mOhm
    D1 (a c a c) relay rclosed=1m vt1=0.0 vt2=1m
    ends idealDiode

    Note that it would not be a good idea to reduce the closed resistance (on resistance) below about 1mOhm; this can lead to convergence problems. You also have to have some small region for the transition - but hopefully this is good enough (with 1mOhm on resistance the current gets up to kA pretty quickly!).

    Then you can use this component:

    Dideal (n1 n2) idealDiode

    Regards,

    Regards,

    Andrew.

Reply

  • The diode model is not intended to be used as an "ideal" diode, so I don't think that's you're best starting point.

    Note - this comes with a bit of caution; modelling "ideal" components is often not a good idea in circuit simulators because they're really not intended for that. For a start, an infinite slope could lead to convergence problems.

    You could implement it with a relay in spectre:

    subckt idealDiode (a c)
    // note, the on resistance shouldn't be below 1mOhm
    D1 (a c a c) relay rclosed=1m vt1=0.0 vt2=1m
    ends idealDiode

    Note that it would not be a good idea to reduce the closed resistance (on resistance) below about 1mOhm; this can lead to convergence problems. You also have to have some small region for the transition - but hopefully this is good enough (with 1mOhm on resistance the current gets up to kA pretty quickly!).

    Then you can use this component:

    Dideal (n1 n2) idealDiode

    Regards,

    Regards,

    Andrew.

Children
No Data

Community Guidelines

The Cadence Design Communities support Cadence users and technologists interacting to exchange ideas, news, technical information, and best practices to solve problems and get the most from Cadence technology. The community is open to everyone, and to provide the most value, we require participants to follow our Community Guidelines that facilitate a quality exchange of ideas and information. By accessing, contributing, using or downloading any materials from the site, you agree to be bound by the full Community Guidelines.