I hope this message finds you well. I am currently measuring the impedance of a microfluidic device, which is within the range of 10M ohms. I have encountered an issue where, for instance, if the impedance measures 8M ohms and I use a 3M ohm resistor for feedback during calibration, I do not obtain the correct impedance value. However, using an 8M ohm resistor for calibration provides an accurate impedance measurement.
I have a few questions:
-
Is it possible to use a single resistor value for feedback calibration to measure impedance ranging from 1 ohm to 10M ohms, thereby overcoming the challenge of frequent calibration? If so, could you please suggest some solutions to address the issue of frequent calibration?
-
I recently read a paper where the author utilized an HMC 245A switch to address the issue of frequent calibration in impedance measurement. Is this method effective? The HMC 245A switch is described as a non-reflective SP3T (Single Pole, Triple Throw) RF switch.
-
Could you recommend a method, switch, or IC that would allow me to measure the impedance of my device from 1 ohm to 10M ohms without needing to change the feedback resistor repeatedly?
Your assistance in this matter would be greatly appreciated.