A capacitive T network calculator in S-math Studio.
Capacitive T Network Calculator
Resistive pads (of the "T" and "PI") varieties are well known and plenty of only caclulators exist for them. For a recent project of mine, I had a need for a capacitive T network calculator. Since I had little success finding one online, I neded-up creation it using the excellent s-math studio mathematical package (free "Mathcad look-alike"). The capacitive T network can be useful for transforming a RC parallel combinaton to an equivalent impedance that depends mostly on the capacitor value (i.e it is insensitve to the R value in parallel with C4) as shown in the following figure. The smath calculator allows the user to change the frequency of operation and the component values (colored "purple" below) and calculates the Zi impedance as seen after the T-pad. Notice in this example how the "transformed" impedance is mostly reactive, with a negligibelcontributuon from the resistor as was the intent.
The following link takes you to a zip file with the smath source file:
Comments, questions, suggestions? You can reach me at: contact (at sign) paulorenato (dot) com