Does anyone know of any instance where the the time constants of two RC circuits in series is additive. It seems that when R1=R2 and tao1~tao2 this holds?
Welcome to the PF.Does anyone know of any instance where the the time constants of two RC circuits in series is additive. It seems that when R1=R2 and tao1~tao2 this holds?
Yes, the PF software is having some issues at the moment. We'll clean up the multiple user names later (it's against the PF rules, but understandable at the moment).That last post (#3) should have been the same as #5 "not thanks to myself" and I don't know what the probelm is, I am also having problems logging back in hence the multiple usernames.
Can you please post some of this work that you've been doing? Thanks.Using a Voigt model to model the circuit indicates that I should only see one time constant the greater of the two, any reason why experimentally I am seeing the sum of the two time constants?
I'm sorry to be dense, but what do you mean by "the two RC circuits are in parallel"? Where are you injecting your signal, and where are you measuring the output signal. And what is the source impedance of your signal generator?The circuitry I have been using is --RC--RC-- where the two RC circuits are in parallel, and the Z'=∑R_k/((1+(ωCR)^2 )) and Z" = -ω∑(CR^2)/((1+(ωCR)^2 )), however upon using this to model the data ie C1=50pF and C2=100pF, R1=R2=1Mohm and sweeping frequency 0.1-100 kHz it is an RC semicircle but the max. gives a tao = 0.1 ms (R2*C2), the experimental data on the other hand, upon subtracting the reference tao C1*R1 from the total tao I get 0.11 ms. I am only trying to determine C2 and I get the right C when subtracting C(total) from C1 but circuit analysis wise I don't see why this works?