Re: Mechanical switch

Go to Text editor file?bounce.asc.

Replace?.lib ..\sym\Source\source.lib to?.lib source.lib

I am sorry.

Bordodynov.

?

Re: Mechanical switch

Hi.
In a packed folder contains files:
bounce.asc
source.lib
bounce.asy
bounce.plt

I rechecked all the (symbol). But netlist showed not the correct link to the library. I was surprised and delete the symbol, and then put it in place. I restarted the file. 
See file bounce.zip (update) in temp folder.
I am sorry.

Bordodynov.


03.08.2016, 13:50, "ericsson.sunshine@... [LTspice]" <ltspice@...>:

Show quoted text

Hi,?Bordodynov:

.lib ..&#92;sym&#92;Source&#92;source.lib

in the file, It can't find this.

Thank you for the file

Best regards.

Re: Modelling an optoisolator

#90019

skipcave wrote:
"I have a requirement to model an optoisolator in LTSpice."

Call me old fashioned, but why don't you start with one of the models in the group's Files section? Use "opto" as a search term and you'll get quite a few hits.

Regards,
Tony

Re: Need help to design a transimpedance amplifier

[email protected]

#90016

Thanks Jim Wagner...

This is what the mistake we made in our previous design...
We had just gone with simulation results and at last got a very noisy amplifier.

Re: Mechanical switch

#90017

Hi,?Bordodynov:

.lib ..\sym\Source\source.lib

in the file, It can't find this.

Thank you for the file

Best regards.

Re: Mechanical switch

#90014

Hi, :

I found a article talking about the breakdown voltage when arcing happens.

At here:

(of course, I am not good at this, it's just discussed. Not sure what's the exact correct answer.)

From the article, it says through the Paschen's law, it could decide the breakdown voltage depends on the distance & gas pressure.It's not linearity.

So under some certain situation (fixed pressure, distance), in the instantaneous time point of the switch on -> off, the contact point where arcing happens should be the most tendency point referring to the "Paschen curve" where pd product is the value at which the breakdown voltage is the lowest.

So the breakdown voltage is able to be estimated, the current flowing through the inductor should be continuous ,supposed it's Ipeak, the instantaneous energy stored in the inductor is 1/2*L*Ipeak^2, and this energy should dissipated through the arcing time, which it's supposed to be V(t)*I(t)*dt (V(0)=breakdown voltage, I(0)=Ipeak, t=0 when arcing happens). Otherwise, maybe there is another path which also consumes the energy.

Just for simple reference.

Appreciate for any opinion to discuss this, so far , I can't find any further article which talking about this on internet.

(But I really like to know more about this.)

Best regards.

?

Re: Thyristor library

#90011

开云体育

Hassan wrote:
"I am new here..."

In that case the suggestion in the welcome message to search the group's Files section will still be fresh in your mind. Had you done this you might have found this:

Additionally, LTspice already comes with SCR and TRIAC symbols in the "Misc" folder.

No need to search "all over the internet"!

Regards,
Tony

Re: Thyristor library

#90013

Hello Hassan.
The fastest way is to download a my folder from LTwiki.org
Go to  and

(A Large LTspice Folder from Bordodynov).
LTC&#92;LTspiceIV&#92;lib&#92;sym&#92;EXTRA&#92;ST&#92;SCR&#92;
LTC&#92;LTspiceIV&#92;lib&#92;sym&#92;EXTRA&#92;ST&#92;TRIAC&#92;
LTC&#92;LTspiceIV&#92;lib&#92;sym&#92;EXTRA&#92;TECCOR&#92;SCR&#92;
LTC&#92;LTspiceIV&#92;lib&#92;sym&#92;EXTRA&#92;TECCOR&#92;TRIAC&#92;

Bordodynov.

03.08.2016, 10:17, "someone00044@... [LTspice]" <ltspice@...>:

Show quoted text

Hello together,
I am new here and I've searched all over the internet to get the full library of a Thyristor but I couldnt :( I have found either the .lib file or the symbol !!! could anybody kindly upload the full library so that we can use it directly. Please feel free to share your experience :)) thanks in advance!
Hassan

Re: Mechanical switch

#90012

Hi.
See file bounce.zip in TEMP folder.

Bordodynov.

03.08.2016, 09:44, "Vlad imbvlad@... [LTspice]" <ltspice@...>:

Show quoted text

There is a spark gap model in the group's files, maybe it can be combined with the bounce relay?

Vlad
______________________
ltspicegoodies.ltwiki.org -- holding, among others:
a universal analog/digital filter, block-level models
for power electronics (and not only), math blocks
with a more stream-lined approach, some digital
ADC, DAC, (synchronous-)counter, JKflop, etc.

Re: Mechanical switch

#90008

There is a spark gap model in the group's files, maybe it can be combined with the bounce relay?

Vlad
______________________
-- holding, among others:
a universal analog/digital filter, block-level models
for power electronics (and not only), math blocks
with a more stream-lined approach, some digital
ADC, DAC, (synchronous-)counter, JKflop, etc.

Re: Current Dependent Voltage Source

#90009

> What if I want to input a table of data I measured from a unit?? I have multiple input/output pairs that I want to use.? How would I do this?

Then you don't need a current/voltage dependent current/voltage source, just a behavioural source or a VCVS/CCVS. For behavioural sources, the syntax is:

table( f(x), time0, value0, time1, value1, ...)? ; f(x) = any time-dependent (or not) quantity

and for CCVSs/VCVSs:

table( time0, value0, time1, value1, ...)? ; the input is implicitly used.

These are assuming you need an input that needs to be passed (transformed) through the table. Otherwise, if all you need is to generate data based on a table, a simpe current/voltage PWL="file" source will do.

Vlad
______________________
-- holding, among others:
a universal analog/digital filter, block-level models
for power electronics (and not only), math blocks
with a more stream-lined approach, some digital
ADC, DAC, (synchronous-)counter, JKflop, etc.

Thyristor library

[email protected]

#90010

Hello together,
I am new here and I've searched all over the internet to get the full library of a Thyristor but I couldnt :( I have found either the .lib file or the symbol !!! could anybody kindly upload the full library so that we can use it directly. Please feel free to share your experience :)) thanks in advance!
Hassan

Re: Mechanical switch

#90006

Hi, :

I guess the question would become ''how to describe the physics behavior about eg. ionization in the air in math equations, and cross voltage before/after acring, and so on..."

I am really interested in those topics, but I can't quite know the terminologies of those topics (about arcing, sparking behavior in physics).

I thinks that's the background knowledge required to built-in the model of spice.

If someone could provide any information about this ?

thank you

Best regards.

---In LTspice@..., <kc6ete@...> wrote :

The bounce is less interesting to me than the spark.? Think kettering ignition system.

Re: Current Dependent Voltage Source

#90005

What if I want to input a table of data I measured from a unit?? I have multiple input/output pairs that I want to use.? How would I do this??

Sent from Yahoo Mail.

On Monday, August 1, 2016 11:50 PM, "Andy ai.egrps@... [LTspice]" wrote:

rmoreno.phone?wrote:

? ?"I've tried to understand how to create a current dependent voltage source but am unable to comprehend how to get my simulation circuit to work.? Is there anything available to describe in detail how to do this?"

Yes; there is the LTspice Help page for H-elements (current-dependent voltage sources).? But most of the reference descriptions there are most helpful for SPICE Netlists, and are a little vague about applying the same syntax to schematic symbols.

Assuming that you are using a schematic:

Voltage sources are our "ammeters".? Put a voltage source (probably set to 0V, but could be non-zero if that fits the rest of your circuit) in the branch where you want to sense the current, that will control your CCVS.

Add an H element where you want it.? Then right-click on the H that is by itself.? Edit that field so that it looks something like this:

Vxxx yyy.y

where Vxxx is the name (reference designator) of the voltage source that is the "ammeter",

and yyy.y is the transresistance or gain (in ?volts/amps) that you want.

Andy

Re: Need help to design a transimpedance amplifier

#90007

开云体育

Unlike a conventional op-amp circuit, the capacitance at the summing junction is extraordinarily important for bandwidth and stability. You can discover this through simulation. Likewise, you can use simulation to explore the requirements for gain-bandwidth product and such. Be aware that often, secondary parameters such as input capacitance are NOT included in simulation models unless the model uses actual transistors for the input stage rather than just a behavioral model.

Jim

James Wagner

Oregon Research Electronics

Show quoted text

On Aug 2, 2016, at 8:49 PM, t.obulesu@... [LTspice] <LTspice@...> wrote:

Thanks for your swift response..?

And whatever the maximum current I can detect upto 5V ...that is fine...?
But I am worrying about how to choose the suitable opamp and design parameters....and resolution should be good...

Re: Mechanical switch

#90004

I tried to sign up normally. Its a catch 22.

Show quoted text

On Aug 2, 2016 9:39 PM, "Andy ai.egrps@... [LTspice]" <LTspice@...> wrote:

?

David,

I don't remember now why you didn't have access to this group's webpages.? I think something was preventing you from signing up the "normal" way, so you had to subscribe via email only.

I think you really ought to subscribe the "normal" way, so you can get access to the group's Files.? Over the last 14 years, there have been questions about contact bounce and about modeling arcing (sparks), and files uploaded about them.? I don't remember how completely those questions were answered.? But I think you might benefit from being able to see those files.

Regards,
Andy

Re: Looking for a IDT74CBTLV3253 model.

#90003

Hello Andy

You wrote :
" Perhaps you are using Firefox, and perhaps you asked Firefox to open
the file in LTspice. Don't do that. "

I think you got it.
I have tried (again) the bad manipulation you described and I got
"multiple instances of? flags"

Regards
PhB

Re: Need help to design a transimpedance amplifier

#90002

To?t.obulesu:

I think you don't have a good understanding of the problem you are trying to solve.? You asked this question twice already.? You got an answer before too, which you apparently ignored.? I get the feeling you do not understand what the constraints and the requirements are.? Your expectations are unrealistic.

FYI, this is not a place to help you design your circuit.? We can help with the simulations, once you have a circuit.

Regards,

Andy

Re: Unable to find InstName attribute in LTSpice for mac

#90001

Hello,

I haben't got an answer from Mike so far.?

In the meantime you could start with an existing symbol like?opamp2 from folder [Opamps].?

Open this symbol and then do a "File->Save as" with the new name.

Now modify this symbol and save it.

Best regards,

Helmut

Re: Need help to design a transimpedance amplifier

[email protected]

#90000

Thanks for your swift response..

And whatever the maximum current I can detect upto 5V ...that is fine...
But I am worrying about how to choose the suitable opamp and design parameters....and resolution should be good...