Interpretation of Bode Magnitude Plots

Let us look now at the circuit in Fig. 2.35, denoted as Rs(Cd (RctCp)), it is described in detail in Exercise 2.12. The impedance of the system is easily written as 

The total impedance can be separated into real and imaginary parts, although the calculations are laborious and it is easy to make a mistake. It can be done easily in Maple (Exercise 2.12), and the obtained impedances are 

To calculate the impedances, either the preceding equations may be used or they can be calculated stepwise in Excel starting from Zf  

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