### Q

As we know that AD5933 can measure both the magnitude and phase of impedance.So, I would like to know if we use this information to estimate the resistance

value and capacitance value when a RC network is being measured. Did you have

any experience or suggestion on this question.

### A

It seems that we are unable to extract the R and C values separately using onlyone excitation frequency from AD5933.

On the other hand, I have added the functions in GUI to display the real and

imaginary contents presented by AD5933. But, I could not find any obvious link

between changes of the two parts and the acupuncture point measured.

1 person found this helpful

Most certainly both R and C values can be calculated from a single-frequency measurement.

If (through proper AD5933 calibration) the magnitude M and phase Ph are measured at a given frequency w, the resistance R and capacitance C can be calculated as follows:

1. For sequential RC network: R = M*Cos{Ph), C = 1 / (w*M*Sin(Ph))

2. For parallel RC network: R = M / Cos(Ph), C = Sin(Ph) / (w*M)