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Behavior transistor models?

Started by Robert Baer September 29, 2014
   Where can one get them, and is there a wide range of transistor type 
represented?

   How good are they, eg: E-B breakdown correct, beta at given sets of 
Ic VS temp correct?, Vbe VS temp and VS Ic correct?
   Are there models for each manufacturer?
In article <m0cek3$ogf$1@speranza.aioe.org>, robertbaer@localnet.com 
says...
> > Where can one get them, and is there a wide range of transistor type > represented? > > How good are they, eg: E-B breakdown correct, beta at given sets of > Ic VS temp correct?, Vbe VS temp and VS Ic correct? > Are there models for each manufacturer?
http://bwrcs.eecs.berkeley.edu/Classes/IcBook/SPICE/UserGuide/elements_f r.html This is a rather good quick reference.. As for the BVbe, so far, at least in Ltspice, that value isn't set in the stock parts and I found a few circuits I had in my junk folder that did not work after setting this parameter. Correction was easy for most of them. if you look at the list of parms you can set, over their default values, it may help in getting a model that gets closer to a real life operation if you're having that type of problem. Someone here helped me with a short cut that became a time saver if you want alter a value a stock model. .model YourNewNameforTheTranny AKO:TheOriginalNameOfTranny BVbe=6 You may already be familiar with this but others may find it interesting. Jamie
On Tuesday, 30 September 2014 06:15:03 UTC+10, Robert Baer  wrote:
> Where can one get them, and is there a wide range of transistor type > represented?
Most manufacturers publish Gummell-Poon models for their transistors. The data can be plugged into LTSpice, and LTSpice includes the Gummell-Poon data for all it's stock transistors.
> How good are they, eg: E-B breakdown correct, beta at given sets of > Ic VS temp correct?, Vbe VS temp and VS Ic correct? > > Are there models for each manufacturer?
Gummel-Poon isn't good at modelling transistors operating in the inverted mode - which is to say using the collector as if it was the emitter and the emitter as if were the collector. VBIC is better, but the model data is commercial-in-confidence. I've never been able to get hold of any. LTSpice can run VBIC models - if you can get the data. -- Bill Sloman, Sydney
Maynard A. Philbrook Jr. wrote:
> In article<m0cek3$ogf$1@speranza.aioe.org>, robertbaer@localnet.com > says... >> >> Where can one get them, and is there a wide range of transistor type >> represented? >> >> How good are they, eg: E-B breakdown correct, beta at given sets of >> Ic VS temp correct?, Vbe VS temp and VS Ic correct? >> Are there models for each manufacturer? > > http://bwrcs.eecs.berkeley.edu/Classes/IcBook/SPICE/UserGuide/elements_f > r.html > > This is a rather good quick reference.. > > As for the BVbe, so far, at least in Ltspice, that value isn't set > in the stock parts and I found a few circuits I had in my junk folder > that did not work after setting this parameter. Correction was easy > for most of them. > > if you look at the list of parms you can set, over their default > values, it may help in getting a model that gets closer to a real life > operation if you're having that type of problem. > > Someone here helped me with a short cut that became a time saver if > you want alter a value a stock model. > > .model YourNewNameforTheTranny AKO:TheOriginalNameOfTranny BVbe=6 > > You may already be familiar with this but others may find it > interesting. > > Jamie
Thanks;been over what you referred to. My main interest is how to describe in a model, beta VS temperature; i think leaving the rest of the stuff alone is OK. Tried beta constant and nothing else specified in a model, a plot of Ib and Vbe looked reasonable from 25C to 204C. So...how does one toss in a curve or data points for beta over temp?
On Mon, 29 Sep 2014 13:15:03 -0700, Robert Baer <robertbaer@localnet.com>  
wrote:

> Where can one get them, and is there a wide range of transistor type > represented? > > How good are they, eg: E-B breakdown correct, beta at given sets of > Ic VS temp correct?, Vbe VS temp and VS Ic correct? > Are there models for each manufacturer?
the best I've seen in terms of accuracy and being able to converge when you use them comes from Alex Bordodynov. He posted all his models for people a while ago, some 35MB of zipped content! I'm pretty sure he matches the models very closely to data sheet. There's a Russian site you can download them from. if you can't find it let me know.
RobertMacy wrote:
> Alex Bordodynov
Found Google Groups, and in middle <quote> Jim Thompson 9/11/13 - show quoted text - Here you go... <http://us.ua/1162032/> Kill the pop-up on the lower left, then you can download. <\quote> Problem is, did not find the pop-up or models (yes, tried the "find" link). Any pointers? Thanks
Robert Baer wrote:
> RobertMacy wrote: >> Alex Bordodynov > Found Google Groups, and in middle > <quote> > Jim Thompson > 9/11/13 > - show quoted text - > Here you go... > > <http://us.ua/1162032/> > > Kill the pop-up on the lower left, then you can download. > <\quote> > Problem is, did not find the pop-up or models (yes, tried the "find" link). > Any pointers? > Thanks >
Well, noodled around a lot and in http://ltwiki.org/index.php5?title=Components_Library_and_Circuits found bjt (308K), dio (102K), jft (106K) and mos (154K) model files. Impressive file sizes, but the BJT models produce linear increasing beta VS temp. I want to see (realistic) curves. How? where?
**Snippie due to aioe limits
> Impressive file sizes, but the BJT models produce linear increasing beta > VS temp. > I want to see (realistic) curves. > How? where?
Measured a few transistors beta VS Ic; anywhere from almost flat to like a hill. Yet another relationship that the models fail to fit. Am guessing the models were meant to work for only one temperature and one collector current.
On Tue, 30 Sep 2014 07:08:06 -0700, RobertMacy <robert.a.macy@gmail.com>
wrote:

>On Mon, 29 Sep 2014 13:15:03 -0700, Robert Baer =
<robertbaer@localnet.com> =20
>wrote: > >> Where can one get them, and is there a wide range of transistor =
type =20
>> represented? >> >> How good are they, eg: E-B breakdown correct, beta at given sets of=
=20
>> Ic VS temp correct?, Vbe VS temp and VS Ic correct? >> Are there models for each manufacturer? > > >the best I've seen in terms of accuracy and being able to converge when =
=20
>you use them comes from Alex Bordodynov. He posted all his models for =20 >people a while ago, some 35MB of zipped content! I'm pretty sure he =20 >matches the models very closely to data sheet. > >There's a Russian site you can download them from. > >if you can't find it let me know.
I would like a copy of that myself. ?-) =20
On Tue, 30 Sep 2014 09:05:42 -0700, Robert Baer <robertbaer@localnet.com>  
wrote:

> RobertMacy wrote: >> Alex Bordodynov > Found Google Groups, and in middle > <quote> > Jim Thompson > 9/11/13 > - show quoted text - > Here you go... > > <http://us.ua/1162032/> > > Kill the pop-up on the lower left, then you can download. > <\quote> > Problem is, did not find the pop-up or models (yes, tried the "find" > link). > Any pointers? > Thanks >
I just sent an email to Alex giving him your localnet.com email address asking him to help you.