I noticed that for an RC filter, the closer the pole is to the jω axis, the smaller the cutoff frequency is, and conversely the further the pole is from the jω axis, a larger cutoff frequency is produced. However, if you take a look at a 3d model of poles/zeros with the σ, jω, and dB axis combined(with the jω axis highlighted to show the frequency response), then a pole close to the jω axis would leave you to believe that a peaking response could occur(which can only happen in higher order filters with complex poles). My question is, how can we show that a real pole with a large value of σ would relate to a large cutoff frequency along the jω axis(and vice versa) yet still retain the characteristic flat lowpass response?
I found the above image from an app note so if someone knows a free program that can provide this type of graph when given a transfer function, I'd greatly appreciate it
I found the above image from an app note so if someone knows a free program that can provide this type of graph when given a transfer function, I'd greatly appreciate it
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