AD5933

https://www.instructables.com/Determining-Body-Composition-using-Arduino. this my circuit and https://github.com/mjmeli/arduino-ad5933 this is code . I insert RFB =1k ohm and Z=3 kohm, output shows 1k ohm only

  • The link to the circuit does not show how the circuit is powered. Is there a split power supply that provides Vdd (+), GND and Vss(-) to this circuit, how the power is wired specifically?
    The gain in this circuit  as designed is supposed to be delivered by the instrumentation amplifier, the two resistors, the one connected between the RFB pin an VIN pin of the AD5933 and the one connected between VIN pin and the output of the instrumentation amplifier, define the gain of the AD5933 internal input OPAMP and, in this circuit, should be of the same value, which could be 10k or 100k instead of 1k just as well.