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Hello John,

The inductance is also a frequency dependent component. Yes, I understand if it'snot air-core, there are many other factors.But that's what we want to achieve, to include the turn-to-turn capacitance, turn-to-housing capacitance, and leakage resistance etc.
I used other EM software to compute the L, then trying to match it with an equation variable freq), then connect with driving circuit.

Regards

Summer

Hello Helmut:

Thanks so much. I downloaded your model and tried in my circuit model. I think it worked. Of course the expression needs to be refined.
So I take it that for inductance, if it's L=4u*(freq/2.5e6)^(-0.5),
then when I use G2 (voltage controlled current),
I should define the value as Laplace=1/(S*L),
is it correct?
In a similar way, capacitance can be defined as well.

Best regards

Summer

Here's a short (but very realistic) subcircuit for a filament type
lamp that has been written for optimum convergence performance in
LTspice:

* Two Pin Incandescent Lamp Model
*
* input: Kc = conductance constant of filament
* input: Kr = radiation constant of filament
* input: CTf = filament thermal capacitance
* input: RTf = filament thermal resistance
* n = numerical dynamic range scale factor
* Cf = filament conductance
* Pf = filament power (electrical input)
* Pr = radiated power (electromagnetic output)
* Tf = filament temperature (in degrees K)
* Ta = ambient temperature (converted to deg K)
*
.subckt Lamp 1 2 params: Kc=120 Kr=.7p CTf=5m RTf=10k
.param n=1m Ta=temp-kelvin ; internal parameters
BCf 1 2 I=V(1,2)*Kc/V(Tf)**1.2
BPf 0 Tf I=V(1,2)*I(BCf)*n
BPr Tf 0 I=Kr*(V(Tf)**4-Ta**4)*n
Cfa Tf Ta {CTf*n} Rpar={RTf/n}
VTa Ta 0 {Ta}
.ends Lamp

It goes fast even with n=0.1 for 325V, lower values seem to take their (minor) toll for longer simulation runs without imposed timestep.

Vlad

Mike,

The new .ini location follows the Windows' one:

/home/<user>/.wine/drive_c/users/<user>/Application Data/.

Personally, I run the clean version the way the installer made the launcher, and the custom version like this:

env WINEPREFIX="/home/<user>/.wine" wine Z:&#92;&#92;opt&#92;&#92;Progs&#92;&#92;LTspiceIV&#92;&#92;scad3.exe -nowine -ini Z:&#92;&#92;opt&#92;&#92;Progs&#92;&#92;LTspiceIV&#92;&#92;scad3.INI

( -nowine because I can resize the components' dialogs, with the downfall of traces when moving symbols -- minor)



Vlad

In message <k1j3en+ith9@...>, dated Tue, 28 Aug 2012, coldcolor0317 <coldcolor0317@...> writes:

Thanks so much for the response. I do want to simulate an AC analysis from 100Hz to 10MHz. The coil is essentially an inductor with a certain value. There's AC resistance too. SO R is increasing with freq, and L is decreasing with freq. I need to model this behavior.

Is this an air-cored inductor? If not, you will have a virtually impossible task to simulate it over that frequency range. It won't be at all easy even if air-cored, because of inter-turn capacitances, current crowding and maybe other factors.

If you want help, holding out on us with 'a certain value' isn't the way to get it.
--
OOO - Own Opinions Only. Try www.jmwa.demon.co.uk and www.isce.org.uk
Instead of saying that the government is doing too little, too late or too
much, too early, say they've got is exactly right, thus throwing them into
total confusion.
John Woodgate, J M Woodgate and Associates, Rayleigh, Essex UK

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

Hi,

I was able to figure it out by opening up the test fixture for the op-amp. Do you know why the put an 11 Ohm resistor on the output of the opamp?

Hello,

The original circuit is on page 1 in the datasheet.

It has a 1:3 transformer driving a 100Ohm transmission line. We
have then an input impedance of 100/3^2=11Ohm on the primary side.
Using a 11Ohm series resistance is a perfect match of this
impedance.
Maybe they removed this transformer in the jigs-example to allow
to simulate the response down to DC.

Best regards,
Helmut

--- In LTspice@..., "coldcolor0317" <coldcolor0317@...> wrote:

Vlad:

Thanks so much for the response. I do want to simulate an AC analysis from 100Hz to 10MHz. The coil is essentially an inductor with a certain value. There's AC resistance too. SO R is increasing with freq, and L is decreasing with freq. I need to model this behavior.
Would you please specify more on how to do it?

Many thanks,

Summer

Hello Summer,

The formula with FREQ doesn't work. You should use a Laplace
function. Below is an example using a G-source.

Laplace=1/(0.95*(s/(2*pi*2.5e6))**0.3+0.1)

I have uploaded an example.

Files > Temp > freq_dep_res.asc

Best regards,
Helmut

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

Hello

R=0.95*(FREQ/2.5e6)^(0.3)+0.1.

This is the way to do it in LTspice, too, unless you want an .AC analysis. If "freq" is some external source, v(freq), it will work. You may need to add curled braces, though.


Good luck,
Vlad

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

Hi,

I was able to figure it out by opening up the test fixture for the op-amp. Do you know why the put an 11 Ohm resistor on the output of the opamp?

Vlad:

Thanks so much for the response. I do want to simulate an AC analysis from 100Hz to 10MHz. The coil is essentially an inductor with a certain value. There's AC resistance too. SO R is increasing with freq, and L is decreasing with freq. I need to model this behavior.
Would you please specify more on how to do it?

Many thanks,

Summer

--- In LTspice@..., rainbowsally <rainbowsally@...> wrote:

Here's how to run ltspice on your windows partition from your linux
partition.
Go here.

Get this. HOW-TO-SCAD3-IN-LINUX.zip

Is there any reason you don't simply install LTspice using Wine?

Maybe I'm misunderstanding what you are doing, but whenevr I need to run LTspice in Ubuntu, I simply download the latest executable and tell Wine to install it. I usually put it in C:&#92;SWCADIII in the Wine folder.

Everything goes exactly the same as in WinXP. There is no need to convert line endings, and I can copy ASC and PLT files back and forth from XP running in VirtualBox to LTspice running in Wine.

The only thing is I don't know where Mike puts the SCAD3.INI file when running in Wine. He moved it from C:&#92;WINDOWS to solve a permissions problem in Win7, and I haven't had the occasion to reinstall LTspice so I don't know where it goes now.

Mike

Hello

R=0.95*(FREQ/2.5e6)^(0.3)+0.1.

This is the way to do it in LTspice, too, unless you want an .AC analysis. If "freq" is some external source, v(freq), it will work. You may need to add curled braces, though.


Good luck,
Vlad

I recommend installing and running it from an ext3(4) partition, it will run faster, updates included.


Vlad

Here's how to run ltspice on your windows partition from your linux partition.
Go here.

Get this. HOW-TO-SCAD3-IN-LINUX.zip

Includes screenshot and the first cut at a utility to clean the database up (currently all caps alphanumerically sorted and removed junky looking unnecessary parentheses around parameters in some of the entries). See the readme.

BTW, the utility is NOT an executable. It's C++ source that you can examine first and compile if you want to check it out.

As a side benefit of not having zero control over what it does, win users might also be interested in compiling it, modifying etc. It sure makes the part lookups easier.

Enjoy! :-)

PS. The makefile is for GCC (linux newlines, not dos crlf's).

Dear LTspice group:

I know there must have been many posts on how to build frequency dependent resistor and inductor for a coil antenna. I know in other software, you can just use an expression with 'freq' as variable to define the component, e.g., R=0.95*(FREQ/2.5e6)^(0.3)+0.1.
Is there any simple way to do it in LTspice? I'm relatively new to the software.

Thanks in advance.

Summer

--- In LTspice@..., "ridethesnake7miles" wrote:

I'm trying to figure out how to model a standard No. 47 flash-
light lamp. I'm having trouble trying to find a similar model.

Here's a short (but very realistic) subcircuit for a filament type
lamp that has been written for optimum convergence performance in
LTspice:

* Two Pin Incandescent Lamp Model
*
* input: Kc = conductance constant of filament
* input: Kr = radiation constant of filament
* input: CTf = filament thermal capacitance
* input: RTf = filament thermal resistance
* n = numerical dynamic range scale factor
* Cf = filament conductance
* Pf = filament power (electrical input)
* Pr = radiated power (electromagnetic output)
* Tf = filament temperature (in degrees K)
* Ta = ambient temperature (converted to deg K)
*
.subckt Lamp 1 2 params: Kc=120 Kr=.7p CTf=5m RTf=10k
.param n=1m Ta=temp-kelvin ; internal parameters
BCf 1 2 I=V(1,2)*Kc/V(Tf)**1.2
BPf 0 Tf I=V(1,2)*I(BCf)*n
BPr Tf 0 I=Kr*(V(Tf)**4-Ta**4)*n
Cfa Tf Ta {CTf*n} Rpar={RTf/n}
VTa Ta 0 {Ta}
.ends Lamp

Look here for a Lamp bulb symbol and a hierarchical model version
of this subcicuit:



LampModel.zip ; incandescent lamp model, symbol, and test files
Lamp.asc ; updated lamp model to replace the one in the zip file

Regards -- analogspiceman

--- In LTspice@..., "afhockey623" <jxm1092@...> wrote:

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Hello,

Maybe something else is setup wrongly fro LTspice.
If you upload your circuit, we might help you.

Best regards,
Helmut

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

--- In LTspice@..., "afhockey623" <jxm1092@> wrote:

Is this an error? I just started using LTspice and I'm trying to use a circuit with an LT1210 and it shows two + supply inputs instead of the usual + and - supply inputs. Thanks gentlemen.

Hello,

Yes, the lower + terminal should be marked -. The models "test circuit" show a negative supply connected to that pin.

Rick

With the circuit I have though no matter how I position the power supplies I am not getting the expected output so I'm not sure if this part is broken or if I need to position them a certain way and that there is actually errors in my circuit.

Good morning Malika,

The first thing you ought to do, is create new messages with an
appropriate Subject, rather than replying to an unrelated message with
a subject that has nothing to do with your question. This makes it
easier for you and others to find your question and replies.

I had used the LTspice, and I found ADG406, but the GND for this integret cicuit is not présent .
PLease, can you help me to find this librery .

I used Google to find the ADG406, and the Analog Devices SPICE model
for it does have a GND pin (pin 12). Just take that pin and connect
it to your circuit's ground node.

Andy

There's a very good lamp model by Helmut in the Files, look for lamp.sub & lamp.asy, you will need to edit the params as required to match your particular lamp.

HTH

Hello

You may want to try the other Yahoo group, "switchmode", they may have the answers you're looking for.


Good luck,
Vlad