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Questions about AD5933 / AD5934

I want to use AD5933 / AD5934.
I'm experimenting, but I'm in trouble because I have some questions.

Please answer  from the items that can be answered.

① The AC output excitation voltage changes depending on the range setting,
What is the purpose of changing the DC output impedance accordingly?

② About CN0217 (EVAL-AD5933EBZ)
Please tell me if there is a way to get logs continuously.
With the attached tool "AD5933 Beta Version REV1.0"
I was able to sweep, but I couldn't get logs continuously.

③ When the component to be measured is replaced from a resistor to a capacitor and measured, the expected system phase angle is recalculated.
Please tell me when and how to calculate the system phase angle.
④ Looking at Table 3 in the "User Guide UG-364", it seems that there is no combination of negative and positive. Is this wrong? 
 Also, the positive / negative formula and the negative / negative formula are the same. Is this also wrong?

https://www.analog.com/media/en/technical-documentation/user-guides/UG-364.pdf#page=23

⑤ The "User Guide UG-364" contains an excerpt from the source code of the evaluation board. Can you provide all the source code?

https://www.analog.com/media/en/technical-documentation/user-guides/UG-364.pdf#page=13

Best Regards,

Naohisa

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  • Hi,

    I'm in trouble...
    We are looking forward to answer from you.

    Best Regards,

    Naohisa

  • I am not affiliated with ADI, so my comments on the chip behavior or documentation are not based on the first-hand knowledge, but since nobody from ADI is responding...

    What is the purpose of changing the DC output impedance accordingly?

    Probably it is not a deliberate feature for a particular purpose, perhaps it would require additional circuits to make the output resistance (and DC level) independent of excitation voltage and that would result in undesirable cost increase.

    Please tell me if there is a way to get logs continuously.

    The chip seems to be designed to perform sweeps. With eval software there is no way of logging continuously, but you can sweep with frequency increment equal to 0, which would give you a log of 511 measurements, but the you would need to restart the sweep to get additional points.

    When the component to be measured is replaced from a resistor to a capacitor and measured, the expected system phase angle is recalculated.

    Not sure what it means. When the resistor is replaced with capacitor, the phase calculated form the values in Re and Im registers rotates by 90°, but the system phase remains the same. When the system is calibrated with a calibration resistor Rcal, which introduces no additional phase, the system phase can be calculated from the values in the Re and Im regusters. This system phase can be taken into account when the phase introduced by an unknown complex impedance by subtracting this system phase form the measured phase.

    Cannot help with #4 and #5, hopefully someone from ADI can chime in.

Reply
  • I am not affiliated with ADI, so my comments on the chip behavior or documentation are not based on the first-hand knowledge, but since nobody from ADI is responding...

    What is the purpose of changing the DC output impedance accordingly?

    Probably it is not a deliberate feature for a particular purpose, perhaps it would require additional circuits to make the output resistance (and DC level) independent of excitation voltage and that would result in undesirable cost increase.

    Please tell me if there is a way to get logs continuously.

    The chip seems to be designed to perform sweeps. With eval software there is no way of logging continuously, but you can sweep with frequency increment equal to 0, which would give you a log of 511 measurements, but the you would need to restart the sweep to get additional points.

    When the component to be measured is replaced from a resistor to a capacitor and measured, the expected system phase angle is recalculated.

    Not sure what it means. When the resistor is replaced with capacitor, the phase calculated form the values in Re and Im registers rotates by 90°, but the system phase remains the same. When the system is calibrated with a calibration resistor Rcal, which introduces no additional phase, the system phase can be calculated from the values in the Re and Im regusters. This system phase can be taken into account when the phase introduced by an unknown complex impedance by subtracting this system phase form the measured phase.

    Cannot help with #4 and #5, hopefully someone from ADI can chime in.

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