Frequency domain simulation issue with phase response

I tried to explore the changes to the frequency response of simple passive RC low pass filters when a second and third cascaded filter section is added.

Unexpectedly, the phase response of the 3rd order filter shows a "jump" in the output.

Why is this?

NB: Please ignore the OpAmp in the circuit.

by Dan.Ka
November 11, 2020

Perfectly normal. When the phase becomes far enough lagging it is leading

by Foxx
November 11, 2020

So you are saying it's just the presentation style of CL's graphing engine. Fair enough.

I prefer, however, the graphing engine to draw phases below - 180° in the negative axis region, as for example here:

https://www.multisim.com/content/nDvUVFQCHVPrhDZSDeYmMU/third-order-rc-low-pass-filter/

by Dan.Ka
November 11, 2020

Yes it's CL's presentation. I have no problem with it once I figured it out

by Foxx
November 12, 2020
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