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opensource transistor database

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nuclearcat:
It looks like my google-fu skills failing me, or i'm looking for something that doesn't exist (but obviously should).
I am making a boost converter, and I am trying to find the optimal transistor and other components for it, and in principle there is nothing difficult to add all the formulas in python script, try each transistor, find optimal circuit values for it, and estimate losses. Then i can make winners list and manually filter out those that dont work for me (price, wrong package type, etc).
But there is a problem, with all the huge selection of transistors, i did not find an opensource database for these transistors, that I could use in such a script.

Doesn't such database really exist?
E.g. where is present transistor model, Coss, V(miller plateu), Vgs, Q (th), and other parameters and it is parseable.

And, maybe if it doesn't exist i should create crowdsourced and opensource database?

T3sl4co1l:
You can get close with the web APIs from several suppliers e.g. Digi-Key, Mouser, etc.

You won't find anything aggregating actual datasheet values unfortunately.  Perhaps scraping mfg websites (perhaps they have APIs too, YMMV) will give more info.

(Otherwise, you're welcome to scrape raw PDFs (probably including OCR as well).  It's... possible.  Feasible?  Good luck... :o )

With queried supplier catalogs, it's rarely necessary to flip through more than a dozen datasheets to find a set of acceptable transistors for a given application.  If you need more, it's a sign that you may be doing something wrong: consider reworking your application to a more conventional approach.  (A counter-example might be, selecting transistors for linear operation: a few use this keyword in their description, but those are expensive; cheaper commodity parts may be rated for DC SOA, but you'll never see those data in the catalog, you have to flip through all the datasheets to find out.  A positive example might be, something dependent on tight or oddball Vgs(th), or tempco or something; these are unreliable parameters and the design should be reconsidered to remove that dependency.)

Miller plateau, by the way, is relative to Vgs(th), and is typical given respective drive conditions (3.3, 4.5, 10V, etc.) and load.  It's certainly nothing you should be sorting by; more likely you'll search to select "logic level" types because of low drive voltage, or exclude because of low Vgs(th) and high Qg (causing very slow turn-off, increasing switching losses).

Tim

kripton2035:
you can search with parameters on
https://octopart.com/electronic-parts/discrete-semiconductors/transistors
or for transistors only here :
https://alltransistors.com/

but no their database is not public, you can have an api access to octopart.(free for small number of search, pay if many searches)

ajb:
A big downside to scraping distributor sites for this info is you'll be relying on how accurately and consistently the distributor has transcribed the datasheet parameters into their database.  The numbers may not be wrong per se, but they may list a value under one set of conditions for one part and a different set of conditions for a different part.  Using data direct from the manufacturer may be more accurate, but you still have to consider the measurement conditions for the parameters you care about, which could be hard to pull out of a datasheet programmatically. Also some datasheets may only specify some parameters via graph. 

I wonder how well machine learning could be applied to pulling all of the graphs out of a datasheet and quantifying them into tables that could then be filtered against.  Even just doing that on SOA plots would be a huge help, like Tim said trying to select a transistor for linear operation is a slog because you have to look at all the datasheets.  I might pay actual money for a tool that would let me enter a set of Id/Vds/t parameters and get a filtered list of parts.

nuclearcat:

--- Quote from: T3sl4co1l on June 18, 2021, 03:34:51 pm ---You can get close with the web APIs from several suppliers e.g. Digi-Key, Mouser, etc.

You won't find anything aggregating actual datasheet values unfortunately.  Perhaps scraping mfg websites (perhaps they have APIs too, YMMV) will give more info.

(Otherwise, you're welcome to scrape raw PDFs (probably including OCR as well).  It's... possible.  Feasible?  Good luck... :o )

With queried supplier catalogs, it's rarely necessary to flip through more than a dozen datasheets to find a set of acceptable transistors for a given application.  If you need more, it's a sign that you may be doing something wrong: consider reworking your application to a more conventional approach.  (A counter-example might be, selecting transistors for linear operation: a few use this keyword in their description, but those are expensive; cheaper commodity parts may be rated for DC SOA, but you'll never see those data in the catalog, you have to flip through all the datasheets to find out.  A positive example might be, something dependent on tight or oddball Vgs(th), or tempco or something; these are unreliable parameters and the design should be reconsidered to remove that dependency.)

Miller plateau, by the way, is relative to Vgs(th), and is typical given respective drive conditions (3.3, 4.5, 10V, etc.) and load.  It's certainly nothing you should be sorting by; more likely you'll search to select "logic level" types because of low drive voltage, or exclude because of low Vgs(th) and high Qg (causing very slow turn-off, increasing switching losses).

Tim

--- End quote ---
Yes, sure i can pick "any" that fits, and it will work, as always design have some margins for each parameter.
But also i like approach "make list of best performers for your application" and pick one i can afford (price and availability mostly), without wasting too much time, plus often i miss some cool models, because i dont like to waste hours on all suppliers, checking parameters of each transistor.
It will be also possible to make python app that will draw parametric curves for SMPS and flip them for each transistor selection by single click of button.
Isn't it cool, if such thing will be possible?

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