AnsweredAssumed Answered

AD5933 evaluation software

Question asked by Hrenovka on Jan 24, 2016
Latest reply on Feb 8, 2016 by mcee

I have solved driver and software problems in another discussion with the awesome help.


Now I'm trying to use the evaluation board EVAL-AD5933EBZ. I went threw the documentation, the schematic to see, which jumpers and connection point are important. I have arranged that but I don't understand threw which pins I'm supposed to measure impedance.

i cannot find the resistor / "RFB" part in the schematic (this one: ) .

But if I lok at the circuit note CN-0217 on using it, the front page with the block diagrams shows me, that the RFB resistor is located in it as the part of inverting stage on A2 and I also confirmed that by following traces with my multi meter. Now, the "Z" pin is the unknown impedance that i want to measure stuff on. Now I want to calibrate the board. When I see calibrating  part of the software, I see R1, R2 and C1. I cannot connect these parts to part on the board / to the open points on the board.


Now what I want to know is, what are R1, R2 and C1 in the relation to part on the board, so I can calculate gain factor / calibrate and proceed to measure and what does the Rfb part / resistor do.


I happy for responses in advance