pulse overshoot ringing spice simulation of pulse through transmission line with IC load

Thread Starter

yef smith

Joined Aug 2, 2020
695
Here,There is a pulse going through a transmission line.There is a phenomena where if we put a pulse through a transmission line then after it reaches the IC we can have ringing instead of good pulse. In LTSPICE simulation connector is represented as pulse voltage source of 6V with resistor in series. Transmission line is represented as RLCG .The load is 2 Ohm because 6V/3A=2Ohm. As you can see i could not get oscillations from this transmission line. I was expecting to see a picture as shown in the end, instead I got in the plot saw shapes which very stable response. Where did I go wrong with this simulation? Thanks.

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crutschow

Joined Mar 14, 2008
34,047
The shown L/C value gives a transmission line characteristic impedance 316 ohms.
Is that what it really is?
How long is the line?
 
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Thread Starter

yef smith

Joined Aug 2, 2020
695
Hello crutschow,Its just me trying to play with the values to get this effect.
Could you please help me with a direction regarding how to build equivalent RLCG so i will get overshoot ringing on the load when i input a pulse?
Thanks.
 

Thread Starter

yef smith

Joined Aug 2, 2020
695
Hello Crutshow, i have done an ADS simultion as shown below i got and overdampted responce.
Your simulation is underdampted responce.
i know that the signal at the load is a sumof wave going back and forth.
Is there a TL theorectical way to predict if i the signal on the load will be overdamped or under dampted?
Thanks.

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