I am working on simulations of a 3rd order RC filter.
Cascaded first order RC lowpass X3 with:R = 100 ohms,C = 3.3 nF.
When I perform the calculations for the transfer function I get a result that is different from the theoretical which is just 3 cascaded 1st order RC filters.
Circuit:
Cascaded:
Calculated:
When I simulate the circuit in LTspice and plot both the above equations in Matlab, the simulation matches the Cascaded formula.
Versus:
Am I deriving the transfer function incorrectly here or is it some other issue?
Full Calculations:
