Brandon's Semiconductor Simulator

(brandonli.net)

187 points | by dominikh 3 days ago ago

20 comments

  • em3rgent0rdr 3 days ago ago

    When spice simulation isn't deep enough... Very educational to show how circuit elements work "under the hood"...for example the LC example doesn't use an L element and a C element as building blocks, but rather it is the two metal plates in close contact which form the bulk of the circuit's capacitance and it is the loop of metal itself which form the inductance.

    • amelius 3 days ago ago

      I wonder how they simulate EM in only 2 dimensions.

      I also wonder why the simulator only allows to show E and D fields, and not H and B.

  • paulgerhardt 3 days ago ago

    Fun. I am reminded of the long forgotten Zachtronics semiconductor game “KOHCTPYKTOP: Engineer of the People” [1]

    [1] https://www.zachtronics.com/kohctpyktop-engineer-of-the-peop...

  • gfody 3 days ago ago

    Sebastian Lague has been making one of these and youtubing it, the videos are great here's the latest one https://www.youtube.com/watch?v=HGkuRp5HfH8

    • gblargg 3 days ago ago

      Note that these are at very different levels of detail. Lague's is at the digital logic level, while Brandon's is some level around atoms/electrons.

  • petermcneeley 3 days ago ago

    Amazing work feels very similar to Paul Falstad page https://www.falstad.com/emstatic/index.html.

    This really needs a WebGPU port. Multigrid on a GPU is moderately easy.

    • 1d22a 3 days ago ago

      The similarity is likely not a coincidence!

      > (c) Brandon Li, 2025. Ported to Javascript with the help of Paul Falstad.

  • westurner 2 days ago ago

    Which other simulators show electron charge density and heat dissipation?

    Can this simulate this?:

    "Synaptic and neural behaviours in a standard silicon transistor" (2025) https://www.nature.com/articles/s41586-025-08742-4 .. https://news.ycombinator.com/item?id=43506198

    What about (graphene) superconductors though?

    • stunningllama 2 days ago ago

      On my info page (https://brandonli.net/semisim/info) there's a list of things my simulation can and can't do. After taking a look at the paper you mentioned, I think simulating it may very well be possible, however it might take a bit of effort. As for graphene, its band structure is different enough that I don't think it would work.

      Note that my simulation is intended for educational purposes only, not scientific research.

      - Brandon

  • spicybright 3 days ago ago

    The UI is rough but this is very impressive!

  • kragen 3 days ago ago

    This looks exciting, but the images make it look like maybe it's two-dimensional?

  • showmexyz 3 days ago ago

    So how accurate are the results?

  • gitroom 3 days ago ago

    im super into stuff like this, takes me back to messing with circuit sims for hours

  • bdbenton5255 3 days ago ago

    Very clean, educational and informative. Well done, from one Brandon to another!

  • 3 days ago ago
    [deleted]
  • cyberspacein 3 days ago ago

    [dead]

  • mhh__ 3 days ago ago

    Really sexy