Hallo, everyone.

For the schematic of the LISN in attachment, could anyone explain why the Inductance and the resistance are in series and both in parallel with the 50 Ohm Resistor?

Wouldn't it be the same to leave the 50 Ohm resistor, if the objective is to have a constant impedance at high frequencies?

Thanks!

FA

P.S. : Not an electric expert, so hope you would excuse me if the question is silly

 

The y m ohm is the resistance of the inductor. Why the 50 ohm ??

 

consider what would be the termination if those resistor aren't there?

 

Hi Sabouras, well...I don't know. Do you have an idea?

 

If the LC which is parallel with the resistance has very high impedance because of the resistor the total resistance of the circuit it will be near to 50ohm. So it will be consider as t 50ohm line. In wikipedia https://en.wikipedia.org/wiki/Line_Impedance_Stabilization_Network
you could see that there are some terminations. As the LISN states An LISN is a low-pass filter typically placed between an AC or DC power source and the EUT (Equipment Under Test) to create a known impedance and to provide a Radio frequency (RF) noise measurement port.
All network analyzers has 50ohm termination so it will be made the measurement. Something similar happened here.
I am not good in explanations but i hope to understand the thoughts and how you must consider the entire circuit.
Best regards.