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--- In LTspice@..., "analogspiceman" <analogspiceman@...> wrote:

Please visit this new page at the LTwiki.



It is still "under construction" and I would appreciate your
suggestions for corrections, omissions noted or improvements
needed. -- a.s.

Hello analogspiceman,

Thanks a lot for collecting all the mile stones.

I always wonder that 1999 was the "birth" of LTspice.
I personally discovered that LTspice is a SPICE program in
the summer 2001. I still believe that I was one of the early
adopters using it as a general SPICE program. Also the
discussions about LTspice started in 2001 in the usenet, sci.electronics.design and sci.electronics.cad.

Best regards,
Helmut

--- In LTspice@..., "oleka111" <oleka111@...> wrote:

Hello,

Running an dc/dc example named 3765.asc with slightly lowered feedback resistor (4.42 --> 4.2k) gives Vout appr. several times bigger than expected.
Just the opposite what we should expect while lowering the feedback resistor.
It can be even dangerous to the sensitive load.

Why it behaves this way ?

Hello,

Well spotted. I have tried this distribution example circuit on two machines, and it behaves as you describe.

I swept the feedback resistor from 4k1 to 4k3 in 10R steps and found that the LTC3766 transitions from closed loop to open loop behaviour when the value goes below 4210R. Whether this a model error or not, I don't know, but the example circuit is clearly unsatisfactory.

I have reported this as a bug to Mike.

Regards,
Tony

Please visit this new page at the LTwiki.



It is still "under construction" and I would appreciate your
suggestions for corrections, omissions noted or improvements
needed. -- a.s.

oleka111 wrote:

Running an dc/dc example named 3765.asc with slightly lowered feedback

resistor (4.42 --> 4.2k) gives Vout appr. several times bigger than
expected.
Just the opposite what we should expect while lowering the feedback
resistor.
It can be even dangerous to the sensitive load.

Why it behaves this way ?

Nobody can answer this because you gave us no information. Try uploading
your complete schematic so we can see what is going on.

Andy

Thank you for pointing that out.
?
I made a mistake in the syntax when I typed it in the message. Yes there is only one pair of inductors in my circuit. Otherwise I would have used Kx (K1, K2,... Kn) in my statement.?
?
cheers,

Hello all,

I am in need of an LTSpice IC model of UC1834 (TI). Anyone who has ever come across one, kindly reply.

In message <1374140838.88699.YahooMailNeo@...>,
dated Thu, 18 Jul 2013, abeillé jean-claude
<jean_claudeabeille@...> writes:

I am a french retired computer analyst and a music and
electonicsenthusiast. Please, will you excuse my english.

It is quite good.

For the moment, I try to understand how does work my amp with LTSpice.
Actually, after an error in handling, one channel failed and activated
a protection circuit (too much quiescent on one output stage polarity).
I tried to fix this but I failed and ordered a complete replacement
PCB. But I am curious and like to understand things. So I drawn the
circuit in LTSpice from the PCB and could not understand it in some places.

Please upload the circuit (we use the US term ''schematic' on this list)
to Files => Temp on the list's web site:

I asked Bob Cordell some help but he was to busy and answer me to read
chapter 1-4 from his book. OK. In fact, in LTSpicen there is almost no
quiescent current in output stage and the VBE spreader does not work at
all. I thought that some models where not correct but I don't know. I'm
deadlocked.

I expect we can help once we see the schematic.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

OK, thank you John.
?Perhaps you can help me in my quest.
I am a french retired computer analyst and a music and electonicsenthusiast. Please, will you excuse my english.
For the moment, I try to understand how does work my amp with LTSpice.
Actually, after an error in handling, one channel failed and activated a protection circuit (too much quiescent on one output stage polarity). I tried to fix this but I failed and ordered a complete replacement PCB.
But I am curious and like to understand things. So I drawn the circuit in LTSpice from the PCB and could not understand it in some places. I asked Bob Cordell some help but he was to busy and answer me to read chapter 1-4 from his book. OK.
In fact, in LTSpicen there is almost no quiescent current in output stage and the VBE spreader does not work at all.
I thought that some models where not correct but I don't know.
I'm deadlocked.

Jean-Claude.





________________________________
De?: John Woodgate <jmw@...>
??: LTspice@...
Envoyé le : Mercredi 17 juillet 2013 18h55
Objet?: Re: [LTspice] MPS4250



?
In message <ks6d15+3s9u@...>, dated Wed, 17 Jul 2013,
jean_claudeabeille <jean_claudeabeille@...> writes:

Can anybody here tell me where I can find a spice model for this PNP ?
Thank you;

Apart from the packaging, it is similar to a BC556 or BC557.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

In message <747691374138968@...>, dated Thu, 18 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

My source files without any corrections you simulated?

Yes, I deleted the first download and downloaded the zip again, opened it and saved all five files to Desktop. I made no changes. The 'Unknown subckt...' error occurred. I opened Core.lib with UltraEdit and copied the .subckt Winding0 to the schematic as a Spice directive. The simulation then ran.

Just to see what would happen, I converted the directive to a comment and the simulation did not run, giving the 'Unknown subckt...' error.

I am using Windows XP SP3, but I don't believe this has anything to do with Windows.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John Woodgate.
My source files without any corrections you simulated?
Bordodynov.

18.07.2013, 12:40, "John Woodgate" <jmw@...>:

In message <256711374134677@...>, dated Thu, 18 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

John Woodgate, I had a similar problem when using the ". inc". It was a month or two ago. I do not remember. I wanted to place the sample in the group, but gave LTspice is the same message as you. I think it bugs LTspice. Then I decided to put the model to the page of the electronic circuit. Then I discovered that you can reference on library in the symbol. Library while in the current folder.
Try to upgrade.

I have version 4.19m, the latest. I can make the simulation run by copying the .subckt to the schematic. I can see that 'winding0' is the VALUE in the symbol Winding0.asy', but I don't see how LTspice knows it should look in Core.lib for the subckt.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John Woodgate, I had a similar problem when using the ". inc".
It was a month or two ago. I do not remember. I wanted to
place the sample in the group, but gave LTspice is the same message as you. I think it bugs LTspice.
Then I decided to put the model to the page of the electronic circuit. Then I discovered that you can reference on library in the symbol. Library while in the current folder.
Try to upgrade.
Bordodynov.

18.07.2013, 11:13, "John Woodgate" <jmw@...>:

In message <622831374124699@...>, dated Thu, 18 Jul 2013, =?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...> writes:

In my example, there is no need to use DOT commands ".inc" and ". Lib".

I know; I was trying to find out why I have the problem.

LTspice allows it. Link to the library name within the symbol "Winding0.asy". Just run the simulation.

It still doesn't run. I will try downloading again.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

Hello,

Running an dc/dc example named 3765.asc with slightly lowered feedback resistor (4.42 --> 4.2k) gives Vout appr. several times bigger than expected.
Just the opposite what we should expect while lowering the feedback resistor.
It can be even dangerous to the sensitive load.

Why it behaves this way ?

Hi.
Look:
.MODEL MPS4250 PNP IS =2.01722E-14 NF=1.00872 VAF =55.5699 IKF= 0.108955 ISE = 6.37359E-16 NE =1.35818 BR =4.41291 NR= 1.02097 VAR= 6.54054 IKR = 0.0178791 ISC =2.78089E-14 NC=1.13928 RB = 85.9809 RE= 0.260437 EG=1.11 XTI = 3 CJE= 9.35999p VJE = 0.805219 MJE= 0.390963 VJC = 0.270529 MJC= 0.295929 FC= 0.5 BF =3.213490E+02 CJC = 6.39675p RC=2.2484 TF=1.0E-10 XTF =1

Bordodynov.

17.07.2013, 20:04, "jean_claudeabeille" <jean_claudeabeille@...>:

--- In LTspice@..., John Woodgate <jmw@...> wrote:

In message <93141374063607@...>, dated Wed, 17 Jul 2013,
=?koi8-r?B?4czFy9PBzsTSIOLP0sTPxNnOz9c=?= <BordodunovAlex@...>
writes:

The model is in the file CORE.LIB. The symbol contains the name of the
library.

Then it's very odd that my computer can't find it. Anyway, thanks for
the explanation.
--
OOO - Own Opinions Only. See www.jmwa.demon.co.uk
Why is the stapler always empty just when you want it?

John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

John,

It worked fine for me. There must be an issue with your PC.

Rick

Hi John Woodgate.
In my example, there is no need to use DOT commands ".inc" and ". Lib". LTspice allows it. Link to the library name within the symbol "Winding0.asy". Just run the simulation.
Bordodynov.

17.07.2013, 20:19, "John Woodgate" <jmw@...>:

Hi Tony,
I just need something for higher frequency, say 10MHz.

--- In LTspice@..., legg@... wrote:

--- In LTspice@..., "sawreyrw" <sawreyrw@> wrote:

--- In LTspice@..., legg@ wrote:

Here's an example of a material exhibiting reduced permeability with frequency.



RL

The link doesn't show anything about permeability vs. frequency.

Rick

Material permeability is directly related to inductance of the sample, if only the frequency changes in the test.

RL

RL,

I understand that, but there is no function of frequency shown at that link. If you don't think that is the case, double check it.

Rick

--- In LTspice@..., "sawreyrw" <sawreyrw@...> wrote:

--- In LTspice@..., legg@ wrote:

Here's an example of a material exhibiting reduced permeability with frequency.



RL

The link doesn't show anything about permeability vs. frequency.

Rick

Material permeability is directly related to inductance of the sample, if only the frequency changes in the test.

RL