TIDUEU6B September 2020 – December 2021 OPA810
Figure 2-6 shows the method to measure the difference voltage across both ZX and RF.
This method nullifies the error due to voltage at the inverting node of A2. Since the voltages across ZX and RF are being measured, this method demands a differential ADC be used for data acquisition. In this design, the accuracies of both methods were verified and found to be the same in the proposed frequencies of operation. High value of Aol (more than 60 dB) of OPA2810 is responsible for this performance.