Hello everybody !! sorry if I pester you with my questions ... but how can I simulate the cat5 or cat6 cable with LTSpice?

 

Do you want to simulate it as a high-frequency transmission line, or just a cable with inductance and capacitance for low frequency signals?

 

hi,
There is a link that may help with the parameters.
E
http://www.mogami.com/e/cad/spice-tline.html
and
https://www.eetimes.com/modeling-category-5-cable-for-dvi-hdmi-links/

 

I have to simulate it at 2 Mb / s.

 

hi,
There is a link that may help with the parameters.
E
http://www.mogami.com/e/cad/spice-tline.html
and
https://www.eetimes.com/modeling-category-5-cable-for-dvi-hdmi-links/

Hi Eric, thanks a lot,
can you help me to insert the parameters in the link you kindly shared with me?
cat 5 and cat6 are cables for a differential signal as you know

 

hi gio,
It is not my area of expertise, so I will have to do a little catch up reading.

I will use this as a starting point.
https://www.maximintegrated.com/en/design/technical-documents/app-notes/5/5141.html

E
A fellow member @Bordodynov may have already created models we can download.??

 

See

 

See
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thanks Bordodynov, can you explain me the parameters you used? r, cws etc (
the parameters you used are those of cat5?) ... the component you used on ltspice to simulate twisted cables what is it called? thanks again for your help

 

Above the symbol of the twisted pair are specified specific parameters (parameters for one meter) - specific resistance of one core - r, specific capacitance between the conductors of the pair - C, specific capacitance between the shield and one conductor - Cws, specific resistance of the screen - Rs. The last value is not given and I took Rs=r/10.
The length of the twisted pair is Len.
When I made the model I didn't know that there are cat5 and cat6 and I took the parameters of some random twisted pair. Now I don't remember which one. It wasn't important to me at the time.
I used the Twisted_pair1024 element. The model consists of 1024 cells.

 

Tks BordodYnov!! but what do you mean by cells? and rs what does it represent?

 

Tks BordodYnov!! but what do you mean by cells? and rs what does it represent?

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Thanks Bordodynov, do you have any links where to find the characteristics of the cat5 cable? I've been looking for 3 hours but I can't find a paper that lists in an exhaustive way the parameters you reported. it's very frustrating

 

hi gio,
The best I have found so far is this data.
https://en.wikipedia.org/wiki/Category_5_cable#Characteristics
E

 

See

 

Thanks!!!!!! i try to simulate!!!

 

I try to simulate but he say missing schematic of hierarchy twisted_pair1024

 

I had the same thing and had to redo the Twisted_pair1024 symbol yesterday. You have an outdated (already) version of the library. Replace it with a new symbol in Long_Line.

 

i simulate this but the time is so long...i must try with less cells...the others old cells works? Twisted_pair 64 for example?

 

It all depends on the length of the twisted pair.
Maybe 32 sections are enough for you. It all depends on the edge of the signal you're transmitting. N=Len is fine.
Why are you giving a sinusoidal signal?

 

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