Good morning everybody,
I`m working on the AD5933 board. I use a AD5933 board to read the impedance. First of all I set up the program inserting the value of the known resistance in the reference of the calibration impedance -resistor value R1-. Afterwards the program reads the correct value of impedance giving a constant value that correspond with the resistor`s one. The problem is that the program doesn`t read the correct value of impedance with another resistance, using the same set up. I have also tried to put two resistors in parallel with 46 kOhm each, and the impedance is not 23 kOhm, as I aspect, but always a constant value a little bit lower than the one of the set up (46kOhm in this case). In other words could somebody tell me each steps to set correctly the program to read the correct impedance?
Thanks in advance
I am sorry about the mark in the Capacitor only position. I have always been running simulation with resistance and never changed that value. By the way, also with the mark in Resistance only position, the results stay as the same as the ones showed in the picture I have sent.
I want you to know that I am inexperienced since this is the first time I am dealing with electronic devices and therefore what I have done so far is following the Technical Notes as close as possible.
What I do in order to measure the impedance is the following:
- the links are connected as follows
LK1, LK2 disconnected: I am not using an external amplifier
LK3 disconnected: I am not using an external clock
LK4, LK5 connected: the ADR433 is the supply to the circuit
LK6, LK7 connected
LK8, LK9 disconnected
LK10, LK11 connected
LK13, LK14 disconnected
- I replaced the 200kOhm resistance with a 5kOhm resistance for the impedance range I am interested in;
- I connected the unknown impedance (that is the calibration resistance) between Vin and Vout.
I have not changed anything else.