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Re: POW(X,Y) doesn鈥檛 work in a function directive with the x**y syntax

Cadinot Didier
 

Thanks a lot Vlad.
You抳e done a very good job
I抳e download your last update Your examples work now
Didier



De : LTspice@... [mailto:LTspice@...] De la part de imbvlad
Envoy� : samedi 20 juillet 2013 07:48
� : LTspice@...
Objet : [LTspice] Re: POW(X,Y) doesn抰 work in a function directive with the x**y syntax



Hello Didier

The reason for that is because of the syntax for .func, it should be by the book:
.func f(x) {...}
not f(x)=...

There may also be some outdated symbols/libraries. I'll make the changes and update the files with the correct syntax later (but possibly much later).

Vlad



[Non-text portions of this message have been removed]
Re: Adding INA105 psipce model into LTspice

[email protected]
 

Hi Helmut,

I truly appreciate your help in resolving the problem. Thank you for attention in this matter and your kind co-operation.

Best Regards,
Shravan krishna

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:



--- In LTspice@..., "shravan.krishna7@" <shravan.krishna7@> wrote:

I am a beginner of LTspice. Please would someone tell the procedure of adding INA105 pspice model into LTspice?

Hello,

I have looked for similar part and found an example with the
INA132. It was easy to modify this part for teh INA105.

Files > Lib > INA105_test.zip


Open the symbol with the symbol editor of LTspice and study
the attributes and the "Netlist order" in the pins. This
netlist order is simply the order of the pins in .subckt.
It's not the name or number of these subcircuit-pins.

Best regards,
Helmut
Re: MPS4250

John Woodgate
 

In message <ksikp7+rtse@...>, dated Mon, 22 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:

I read the first part of B. Cordell's book but didn't found there the explanations of the basic principles of the amp's operating mode. And that, after reading a lot in books and sites. Do you know where I can find this kind of information since everyboby here, like you, is saying it's off-topic - which I understand - while I realize that all these persons get the knowledge. I don't want to intrude any longer.
This site is helpful, and the information is largely reliable:



This one is mostly good, too:



Unfortunately, there are many other sites that give much less reliable and useful information.
--
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
Re: MPS4250

jean_claudeabeille
 

Thank you, Andy, the answers were clear.

I read the first part of B. Cordell's book but didn't found there the explanations of the basic principles of the amp's operating mode. And that, after reading a lot in books and sites.
Do you know where I can find this kind of information since everyboby here, like you, is saying it's off-topic - which I understand - while I realize that all these persons get the knowledge. I don't want to intrude any longer.

--- In LTspice@..., Andy <Andrew.Ingraham@...> wrote:

jean_claudeabeille wrote:

I uploaded the new corrected one along with the missing components files :
AmpJCA.zip.
I hope that this time the schematic is correct.
Still has errors.

Still missing the LF353. LTspice is looking for the schematic symbol (.asy
file).

Needs a statement to include the special "standard.bjt" file.

Meanwhile I received 2 models of mps4250. Simulations with one of them and
with BC557
give very different results. Which one is true ?

Probably both ... or neither.

Remember all components have tolerances, which for some transistor
parameters can be on the order of +/-100% or so (well, +100%, -50%, or
more).

In fact results are very dependent of model's parameters.
That's unfortunate. A good amplifier design ought to make the results
largely independent of model parameters, over a reasonable range.


Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which
is not present in LTSpice's OPTOS.
As long as you include a model for the CNY17-4, it's OK.


What I woud like to understand is HOW to equilibrate the voltages at the
collectors of Q12 and Q13 to get quite the same current at R101 and R111.
Here's where the discussion becomes off-topic for this forum, because we
are now talking about amplifier design, rather than circuit simulation.

One would use the trimmer 1K resistor to set the quiescent (static)
currents through R101 and R111.

To get equal currents through R101 and R111, that should happen
automatically. As long as no current goes out to the load, all the current
through R101 flows through R111. To get no quiescent current to the load,
trim the input offset voltage so that the output pin sits at 0V when the
input is 0V.

Regards,
Andy


[Non-text portions of this message have been removed]
Re: Step Change to k of Coupled Inductors During Transient Analysis

 

Hi Bryan.
Look Mutual_Inductance_K=F(V)_V2.zip in /TEMP
In my case, made 鈥嬧�媡wo related inductance of the four sub-schemes and four nonlinear resistors. The coupling coefficient is equal to inductance circuit voltage at node "K". The restriction 0 <K <1. I made "K" time dependent with PWL-source. "K" is changed from 0.9 to 0.1.
Each consists of two inductor. Their sum remains constant, as shown by the current.
Bordodynov.

20.07.2013, 11:06, "bryan.esteban@..." <bryan.esteban@...>:

Greetings,

I'm interested in applying a step change to the coupling coefficient of two coupled inductors during transient analysis at a desired time. Is this something that can be done using the .func & .param commands?

Thanks in advance for any assistance rendered.

Bryan
Re: Step Change to k of Coupled Inductors During Transient Analysis

 

John,

Thanks for the follow-up question.

Bryan

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

In message <ksdlam+2tic@...>, dated Sat, 20 Jul 2013, Helmut
<helmutsennewald@...> writes:

The answer is no.
Everything defined with .param will be evaluated at the beginning of a
simulation and is then constant for the whole simulation.
But is there another way to change K at a specified time during a .tran
simulation?
--
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
Re: Step Change to k of Coupled Inductors During Transient Analysis

 

Helmut,

Thanks for your initial response and later addition on the possible alternative.


Bryan

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:



--- In LTspice@..., "bryan.esteban@" <bryan.esteban@> wrote:

Greetings,

I'm interested in applying a step change to the coupling coefficient of two coupled inductors during transient analysis at a desired time. Is this something that can be done using the .func & .param commands?

Thanks in advance for any assistance rendered.

Bryan

Hello Bryan,

The answer is no.
Everything defined with .param will be evaluated at the beginning
of a simulation and is then constant for the whole simulation.

Best regards,
Helmut
Re: MPS4250

 

jean_claudeabeille wrote:

I uploaded the new corrected one along with the missing components files :
AmpJCA.zip.
I hope that this time the schematic is correct.
Still has errors.

Still missing the LF353. LTspice is looking for the schematic symbol (.asy
file).

Needs a statement to include the special "standard.bjt" file.

Meanwhile I received 2 models of mps4250. Simulations with one of them and
with BC557
give very different results. Which one is true ?

Probably both ... or neither.

Remember all components have tolerances, which for some transistor
parameters can be on the order of +/-100% or so (well, +100%, -50%, or
more).

In fact results are very dependent of model's parameters.
That's unfortunate. A good amplifier design ought to make the results
largely independent of model parameters, over a reasonable range.


Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which
is not present in LTSpice's OPTOS.
As long as you include a model for the CNY17-4, it's OK.


What I woud like to understand is HOW to equilibrate the voltages at the
collectors of Q12 and Q13 to get quite the same current at R101 and R111.
Here's where the discussion becomes off-topic for this forum, because we
are now talking about amplifier design, rather than circuit simulation.

One would use the trimmer 1K resistor to set the quiescent (static)
currents through R101 and R111.

To get equal currents through R101 and R111, that should happen
automatically. As long as no current goes out to the load, all the current
through R101 flows through R111. To get no quiescent current to the load,
trim the input offset voltage so that the output pin sits at 0V when the
input is 0V.

Regards,
Andy
Re: MPS4250

jean_claudeabeille
 

thank you Helmut for your patience and answers. Now, it's more clear in my mind.
Besides, some answers didn't satisfy me : R4 and especially D4 and R12. How does my amp can work since it is in this configuration ?
If I figure it out well, electronics can only be understood by practicing but certainly not by reading books like I do. Silly of me.

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

Hello Jean,

My answers are below.

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

OK. I agree, on your schematic, the amp works fine. Problem is :
why did you changed, added components and changed some wires :
- output on R4 in place of C5
R4 has to be ideally connected to the output as I did. Then the
offset of the amplifier output will be only the offset of U1B.
If we connect R4to the net "C5", the offset of U1B will be
multiplied by the gain 25 of the amplifier.


- D5 instead of Q5
I don't have the model parameters for a Vbe breakdown. You also
don't know what breakdown voltage you get. 7v, 8V, 9V?

- D4 added
1.5V of one LED is too less.

- Q11 PNP instead of NPN
You had a NPN symbol but named it a PNP. That's a "foul play". :-)
The simulation will simply not work as intended.
I replaced it with a PNP to leave the PNP-type. Alternatively
one could had rename the NPN with a NPN-type.

- U1A output connected to I-
- deleted R12.
I have shown the only correct usage of unused opamps. To make
this even more save, connect a 10k resistor between GND and
the +input of U1A. (I had forgot this resistor.)

This is not the real schematic, the one I uploaded.

What does mean : "Watch this voltage. Select R5!" ?
You should look that the opamp output U1B is not at the rails.
If this is the case and your circuit is correctly wired, you
should try a slightly larger or lower value of R5 to bring the
opamp output into its linear region.


I understand nothing about this :" This control loop has to be slower then the lower corner frequency of your amplifier". Can you develop this ?
At very low frequency of a few Hz, this loop will cancel your
AC audio signal. It will behave like having a highpass with
a few Hz in the input.

How do you worked to get this solution ? What is the trick ?
I have 35 years experience with analog circuit design.

At last, what is the job of D3/D107,
It limits the input differential voltage during power-up
and down or if somebody connects an AC-coupled pre-amplifier
or the input voltage is faster than the amplifier can follow..

D102/D103.
They avoid that you expensive amplifier will be destroyed due
to reverse bias during power-up and down.

I apologize wasting your time with so basic questions,
but I try to understand.
I read the first part of B. Cordell's book and learn a lot
but not enough to understand this damn amp. I asked some
help to B. Cordell but he answered to read chapters 1-4.
Am I stupid or something?
You had made a mix of a few schematic drawing mistakes and a
very few design errors. The combination makes it hard to get
the first working simulation. Now it's working.

PS:
I like the idea with Q14. It limits the maximum current of Q8.

Best regards,
Helmut
Re: MPS4250

 

Macy wrote:

.model PN4250 PNP(Is=6.734f Xti=3 Eg=1.11 Vaf=45.7 Bf=388.2 Ne=1.806
...

hmmm...don't need the parentheses anymore eh?
Parentheses were never needed there. Unless I am mistaken, they are
treated like whitespace. This goes back to the 1970s (Berkeley SPICE).

There are some places where parentheses are mandatory, but a .MODEL
statement is not one of them.

They are harmless, so it can be useful to add them, to show that the entire
enclosed text is a list of parameters.

Andy
Re: LTspice World Tour in Australia

John Woodgate
 

In message <kshfhj+al36@...>, dated Sun, 21 Jul 2013, Helmut <helmutsennewald@...> writes:

I want only remind that Mike is on tour in Australia this week.
That will compensate them for losing the first two cricket Test Matches, but not 100%. (;-)
--
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
LTspice World Tour in Australia

 

Hello,

I want only remind that Mike is on tour in Australia this week.






Best regards,
Helmut
Re: MPS4250

 

Hello Jean,

My answers are below.

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

OK. I agree, on your schematic, the amp works fine. Problem is :
why did you changed, added components and changed some wires :
- output on R4 in place of C5
R4 has to be ideally connected to the output as I did. Then the
offset of the amplifier output will be only the offset of U1B.
If we connect R4to the net "C5", the offset of U1B will be
multiplied by the gain 25 of the amplifier.


- D5 instead of Q5
I don't have the model parameters for a Vbe breakdown. You also
don't know what breakdown voltage you get. 7v, 8V, 9V?

- D4 added
1.5V of one LED is too less.

- Q11 PNP instead of NPN
You had a NPN symbol but named it a PNP. That's a "foul play". :-)
The simulation will simply not work as intended.
I replaced it with a PNP to leave the PNP-type. Alternatively
one could had rename the NPN with a NPN-type.

- U1A output connected to I-
- deleted R12.
I have shown the only correct usage of unused opamps. To make
this even more save, connect a 10k resistor between GND and
the +input of U1A. (I had forgot this resistor.)

This is not the real schematic, the one I uploaded.

What does mean : "Watch this voltage. Select R5!" ?
You should look that the opamp output U1B is not at the rails.
If this is the case and your circuit is correctly wired, you
should try a slightly larger or lower value of R5 to bring the
opamp output into its linear region.


I understand nothing about this :" This control loop has to be slower then the lower corner frequency of your amplifier". Can you develop this ?
At very low frequency of a few Hz, this loop will cancel your
AC audio signal. It will behave like having a highpass with
a few Hz in the input.

How do you worked to get this solution ? What is the trick ?
I have 35 years experience with analog circuit design.

At last, what is the job of D3/D107,
It limits the input differential voltage during power-up
and down or if somebody connects an AC-coupled pre-amplifier
or the input voltage is faster than the amplifier can follow..

D102/D103.
They avoid that you expensive amplifier will be destroyed due
to reverse bias during power-up and down.

I apologize wasting your time with so basic questions,
but I try to understand.
I read the first part of B. Cordell's book and learn a lot
but not enough to understand this damn amp. I asked some
help to B. Cordell but he answered to read chapters 1-4.
Am I stupid or something?
You had made a mix of a few schematic drawing mistakes and a
very few design errors. The combination makes it hard to get
the first working simulation. Now it's working.

PS:
I like the idea with Q14. It limits the maximum current of Q8.

Best regards,
Helmut
Re: LTspice Genealogy - The Heritage of Simulation Ubiquity

 



Simulation Program with Integrated Circuit Emphasis

-----Original Message-----
From: LTspice@... [mailto:LTspice@...] On Behalf Of
Henry McCall
Sent: Saturday, July 20, 2013 1:27 PM
To: LTspice@...
Subject: Re: [LTspice] Re: LTspice Genealogy - The Heritage of Simulation
Ubiquity

The grandfather of all spice programs was a phd thesis in one of the
California universities.
it was even called spice which indicated a ( S? Program for Integrated
Circuit Engineering.)
it's primary purpose was mos circuits as I recall. It was mid to late
60's I think.


On 7/20/2013 1:16 PM, John Woodgate wrote:
In message <kseg1d+mptm@...>, dated Sat, 20 Jul 2013,
legg@... writes:

Mind you, there are spice era files from (likely) elsewhere that
predate these - mostly libraries. The same file type from a Basso
Pspice CD install is marked Nov98.
It's normally completely impossible to know when anything really
started. I know that an ex-colleague was doing simulations at Kings
College, London of audio circuits using FORTRAN with matrices no later
than early 1964 (because that's when the lab caught fire).


------------------------------------

Yahoo! Groups Links
Re: MPS4250

jean_claudeabeille
 

OK. I agree, on your schematic, the amp works fine. Problem is : why did you changed, added components and changed some wires :
- output on R4 in place of C5
- D5 instead of Q5
- D4 added
- Q11 PNP instead of NPN
- U1A output connected to I-
- deleted R12.
This is not the real schematic, the one I uploaded.

What does mean : "Watch this voltage. Select R5!" ?

I understand nothing about this :" This control loop has to be slower then the lower corner frequency of your amplifier". Can you develop this ?

How do you worked to get this solution ? What is the trick ?

At last, what is the job of D3/D107, D102/D103.

I apologize wasting your time with so basic questions, but I try to understand.
I read the first part of B. Cordell's book and learn a lot but not enough to understand this damn amp. I asked some help to B. Cordell but he answered to read chapaers 1-4.
Am I stupid or something ?

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

Hello Jean,

I have uploaded a new version which tries to use most of your
original values while still has all the necessary corrections.
Please continue with this version in your project.

Files > Temp > AmpJCA_1b.zip

The LF353 regulates the DC-output voltage to the DC-input
voltage. Therefore the opamp adjusts the current of the JFets
which changes the voltage drop on R5. Basically it equalize the
collector current of Q8 and Q12. This control loop has to be
slower then the lower corner frequency of your amplifier.

Best regards,
Helmut

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


Hello John

You are right, there are some errors in the schematic.
I uploaded the new corrected one along with the missing components files : AmpJCA.zip.
I hope that this time the schematic is correct.

Meanwhile I received 2 models of mps4250. Simulations with one of them and with BC557
give very different results. Which one is true ? LTSpice's one - BC557B or BC557C - I guess.
In fact results are very dependent of model's parameters.
Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which is not present in LTSpice's OPTOS.

What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111.

--- In LTspice@..., "Helmut" <helmutsennewald@> wrote:

--- In LTspice@..., abeill脙漏 jean-claude <jean_claudeabeille@> wrote:

Thank you for the tutorial, I wouldn't have found out in what
folder - temp - to store the file.
OK, it's done, file name is AmpJCA.asc.
Hello Jean,

The circuit had a lot of mistakes. I tried to correct them.
Please watch all the circles and my other comments in the
schematic. My files:

Files > Temp > AmpJCA_1.zip

I have used most of the missing transistor models from
bordodynov's file standard.zip.


Over all we don't want discuss the design of audio amplifiers
in the LTspice Yahoo group. You should do that in DiY-Audio
groups. There are also books about audio amplifiers, e.g.
this one from Cordell, .

Best regards,
Helmut
Re: MPS4250

jean_claudeabeille
 

OK, thank you

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

In message <ksg876+8t42@...>, dated Sun, 21 Jul 2013,
jean_claudeabeille <jean_claudeabeille@...> writes:

What I woud like to understand is HOW to equilibrate the voltages at
the collectors of Q12 and Q13 to get quite the same current at R101 and
R111.
I suggest you follow Helmut's advice, because your question is about
amplifier design, not LTspice simulation.
--
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
Re: MPS4250

 

Hello Jean,

I have uploaded a new version which tries to use most of your
original values while still has all the necessary corrections.
Please continue with this version in your project.

Files > Temp > AmpJCA_1b.zip

The LF353 regulates the DC-output voltage to the DC-input
voltage. Therefore the opamp adjusts the current of the JFets
which changes the voltage drop on R5. Basically it equalize the
collector current of Q8 and Q12. This control loop has to be
slower then the lower corner frequency of your amplifier.

Best regards,
Helmut

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


Hello John

You are right, there are some errors in the schematic.
I uploaded the new corrected one along with the missing components files : AmpJCA.zip.
I hope that this time the schematic is correct.

Meanwhile I received 2 models of mps4250. Simulations with one of them and with BC557
give very different results. Which one is true ? LTSpice's one - BC557B or BC557C - I guess.
In fact results are very dependent of model's parameters.
Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which is not present in LTSpice's OPTOS.

What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111.

--- In LTspice@..., "Helmut" <helmutsennewald@> wrote:

--- In LTspice@..., abeill脙漏 jean-claude <jean_claudeabeille@> wrote:

Thank you for the tutorial, I wouldn't have found out in what
folder - temp - to store the file.
OK, it's done, file name is AmpJCA.asc.
Hello Jean,

The circuit had a lot of mistakes. I tried to correct them.
Please watch all the circles and my other comments in the
schematic. My files:

Files > Temp > AmpJCA_1.zip

I have used most of the missing transistor models from
bordodynov's file standard.zip.


Over all we don't want discuss the design of audio amplifiers
in the LTspice Yahoo group. You should do that in DiY-Audio
groups. There are also books about audio amplifiers, e.g.
this one from Cordell, .

Best regards,
Helmut
Re: MPS4250

John Woodgate
 

In message <ksg876+8t42@...>, dated Sun, 21 Jul 2013, jean_claudeabeille <jean_claudeabeille@...> writes:

What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111.
I suggest you follow Helmut's advice, because your question is about amplifier design, not LTspice simulation.
--
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
Re: MPS4250

jean_claudeabeille
 

OK, Helmut, if "we don't want discuss the design of audio amplifiers", I give up !

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

--- In LTspice@..., abeill脙漏 jean-claude <jean_claudeabeille@> wrote:

Thank you for the tutorial, I wouldn't have found out in what
folder - temp - to store the file.
OK, it's done, file name is AmpJCA.asc.
Hello Jean,

The circuit had a lot of mistakes. I tried to correct them.
Please watch all the circles and my other comments in the
schematic. My files:

Files > Temp > AmpJCA_1.zip

I have used most of the missing transistor models from
bordodynov's file standard.zip.


Over all we don't want discuss the design of audio amplifiers
in the LTspice Yahoo group. You should do that in DiY-Audio
groups. There are also books about audio amplifiers, e.g.
this one from Cordell, .

Best regards,
Helmut
Re: MPS4250

jean_claudeabeille
 

Hello John

You are right, there are some errors in the schematic.
I uploaded the new corrected one along with the missing components files : AmpJCA.zip.
I hope that this time the schematic is correct.

Meanwhile I received 2 models of mps4250. Simulations with one of them and with BC557
give very different results. Which one is true ? LTSpice's one - BC557B or BC557C - I guess.
In fact results are very dependent of model's parameters.
Besides, I don't know if it's important but on my amp, U2 is CNY17-4 which is not present in LTSpice's OPTOS.

What I woud like to understand is HOW to equilibrate the voltages at the collectors of Q12 and Q13 to get quite the same current at R101 and R111.

--- In LTspice@..., "Helmut" <helmutsennewald@...> wrote:

--- In LTspice@..., abeill脙漏 jean-claude <jean_claudeabeille@> wrote:

Thank you for the tutorial, I wouldn't have found out in what
folder - temp - to store the file.
OK, it's done, file name is AmpJCA.asc.
Hello Jean,

The circuit had a lot of mistakes. I tried to correct them.
Please watch all the circles and my other comments in the
schematic. My files:

Files > Temp > AmpJCA_1.zip

I have used most of the missing transistor models from
bordodynov's file standard.zip.


Over all we don't want discuss the design of audio amplifiers
in the LTspice Yahoo group. You should do that in DiY-Audio
groups. There are also books about audio amplifiers, e.g.
this one from Cordell, .

Best regards,
Helmut
93321 - 93340 of 157862