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#analog-design
Title
# analog-design
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Paul Schulz

08/12/2020, 3:07 AM
@User @User Do you know what level TCAD start with? Do they begin with discrete Mawxell equations, or an effective approximation? or even a particle based model.
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jrsharp

08/12/2020, 3:10 AM
@Paul Schulz at the most basic level, TCAD programs (like Genius, Sentaurus) are drift diffusion solvers, not Maxwell solvers
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Paul Schulz

08/12/2020, 3:10 AM
@jrsharp Thanks
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jrsharp

08/12/2020, 3:13 AM
I think Sentaurus can do ray tracing simulations of optics, not sure if it has a Maxwell solver though
if you're unfamilar with semiconductor modelling, something like this might help: https://link.springer.com/chapter/10.1007/978-3-7091-6961-2_4
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Paul Schulz

08/12/2020, 3:15 AM
@jrsharp Thanks again. It was more of a general question. I'm still trying to work out where we are with the software. My background (education) is in Mathematical Physics/Particle Physics, but i ended up working in Linux System Administration. Currently not working, but I'm keen to do something with the SkyWater 130nm.
Hmm.. that looks interestig.
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jrsharp

08/12/2020, 3:18 AM
@Paul Schulz you're welcome. The most basic models for semiconductors come from a kind of semi-classical theory. As devices become smaller and smaller, models become more and more quantum mechanics related. But it's been a while since I modelled semiconductor devices so my memory is rather vague 🙂
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Paul Schulz

08/12/2020, 3:18 AM
I am currently listening to the ABC (Australian Broadcaster) radio, and they are broadcasting the Canberra Press Club, currently talking to CSIRO Boss. Lots of talk about commercialisation, philanthropy, but nothing at all about Free and Open Source in innovation.
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jrsharp

08/12/2020, 3:19 AM
Larry Marshall? I don't think he's into open source 🙂
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Paul Schulz

08/12/2020, 3:19 AM
Yeah.. nah
All for other people being philanthropic.
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jrsharp

08/12/2020, 3:20 AM
He's crazy into hydrogen these days, hydrogen airliners is gonna be the next thing 🙂
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Paul Schulz

08/12/2020, 3:24 AM
I don't mind hydrogen. Apparently we are producing too much solar power in South Australia when the sun shines and the win does blow (insufficient load).. having a hydrogen plant that can use the surplus would be ideal (or some other switchable load), rather than the discussion about de-rating wind and turning off home solar remotely.
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jrsharp

08/12/2020, 3:24 AM
If only the Morrison government believed in climate change eh?
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Paul Schulz

08/12/2020, 3:25 AM
Yeah.. even a dose of 'common good' would be nice.
Where are you?
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jrsharp

08/12/2020, 3:26 AM
Would you believe, Hobart 🙂
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Paul Schulz

08/12/2020, 3:27 AM
Good on you! Adelaide here.
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jrsharp

08/12/2020, 3:27 AM
I consider myself quite lucky, as I'm originally from Melbourne. Wouldn't want to be there now.
Adelaide is a nice place. I like SA wines
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Paul Schulz

08/12/2020, 3:28 AM
I had to go to Brisbane 3 weeks ago for my Dad funeral. I was in the area (Ipswitch) where the two girls ended up.
SA Wines are awesome.
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jrsharp

08/12/2020, 3:28 AM
Oh no, did you have to quarantine?
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Paul Schulz

08/12/2020, 3:29 AM
No. I got out before that came in.
Went to get a test but was going to have to wait 3 hrs. The ABC then published more details about where they went, which was nowhere near where I had been, thank goodness.
I left and isolated as well as I could at home. No symtoms of anything.
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jrsharp

08/12/2020, 3:31 AM
Well, that's a relief.
What kind of ASIC are you hoping to produce?
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Paul Schulz

08/12/2020, 3:32 AM
.. and no-one around me has got sick (just in case I was non-symtomatic)
Good question.
I was thinking of something for a conference badge, but have been asking around.
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jrsharp

08/12/2020, 3:33 AM
That would be cool.
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Paul Schulz

08/12/2020, 3:33 AM
Someone I know wants an LED driver for their lego trains. With current limiting and monitoring.
Something IoT related would be good (a LoRaWAN sensor of some description, low power)
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jrsharp

08/12/2020, 3:34 AM
Those are interesting ideas.
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Paul Schulz

08/12/2020, 3:35 AM
I was struggling to get into it, but it's still early days.
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jrsharp

08/12/2020, 3:35 AM
From my point of view, I can't do anything without the device models.
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Paul Schulz

08/12/2020, 3:35 AM
I would also love to see some implementations on some historical systems.. eg. transputer, lisp machine
What are you after?
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jrsharp

08/12/2020, 3:36 AM
For example, I put a simple verilog design through the OpenLane tool, but when I reviewed the netlist, I was sceptical about the results... and without device models I can't do functional verification or SPICE
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Paul Schulz

08/12/2020, 3:36 AM
Oh yes.. a large (?) 8x8 coincidence detector for a muon detector.
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jrsharp

08/12/2020, 3:37 AM
That would be cool
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Paul Schulz

08/12/2020, 3:37 AM
Now.. OpenLane, can that be used to produce arrays of cells?
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jrsharp

08/12/2020, 3:37 AM
It's a RTL to GDS compiler, for digital logic
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Paul Schulz

08/12/2020, 3:38 AM
or is OpenLane more 'here is a function, implement it in silicon'?
Ok
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jrsharp

08/12/2020, 3:38 AM
yes it takes RTL (register transfer logic/ level/ language) and converts it to a digital circuit
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Paul Schulz

08/12/2020, 3:39 AM
I finally found the 'technology file' in open_pdks 🙂 Now my spice looks a lot better.
(Via a tutorial video yeaterday)
Just need to find it again.
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jrsharp

08/12/2020, 3:40 AM
Cool
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Paul Schulz

08/12/2020, 3:40 AM
Thanks for the chat.
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jrsharp

08/12/2020, 3:40 AM
No problem
just message me if you have any questions about semiconductor theory
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Paul Schulz

08/12/2020, 3:58 AM
Thanks... I'm adding you to my 'usefule people' list.
I WILL have a bunch of questions.