RF Current Probes Episode 3 - Understanding Transfer Impedance

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  • เผยแพร่เมื่อ 25 ม.ค. 2025

ความคิดเห็น • 7

  • @tapanprsd1
    @tapanprsd1 5 หลายเดือนก่อน

    Hi, May you please explain why the capacitance "C6" (in 1st case 15:17) is higher than "C2" (in 2nd case 17:35).

    • @MachOneDesignEMC
      @MachOneDesignEMC  5 หลายเดือนก่อน +1

      Well spotted, 6p and 20p are not so much difference for the results (for Low frequency), I think I may have two sim models there and I chose different values when I was building the models. I should have used the same value for consistency. Many thanks

  • @MJ-vt1kp
    @MJ-vt1kp 6 หลายเดือนก่อน

    Good job :)

  • @mustafeezulhassan8604
    @mustafeezulhassan8604 2 หลายเดือนก่อน

    Lets say I have a current probe capable of measuring 350A( DC-60Hz), with transfer impedance of 1ohm. Now terminating the oscilloscope at 50 ohms means I should read (350)*(1)=350V on the oscilloscope, which definitely is not possible because of lower voltage measuring capability at 50 ohms termination. Please guide how can we use a Current Probe in this condition. Thanks

    • @mustafeezulhassan8604
      @mustafeezulhassan8604 2 หลายเดือนก่อน

      Can I actually use a current probe to measure DM current in 100s of Amperes? I suppose yes, but that leads to the above problem.

    • @MachOneDesignEMC
      @MachOneDesignEMC  หลายเดือนก่อน

      good question Mustaf, most likely the probe will saturate, I am sure some manufacturers can have a design to improve their current rating, but that often at a cost. Also, for such probes, you will probably not get 1 ohm as transfer impedance, they are most likely like 0.01 ohm or something like that.

    • @MachOneDesignEMC
      @MachOneDesignEMC  หลายเดือนก่อน

      actually, I just looked it up, Tekbox will soon have one probe that is capable of taking bias current up to 200 A without getting saturated, and the transfer impedance is about 11 dbohm, but they also recommend only use the probe to measure RF noise, the current rating is really there to ensure the probe does not get saturated. So I guess if you want to use a probe to measure accurately on DC to a few hundred hertz, best is to use a Hall effect based probe.