A blog so big it needed two parts.
This time it's all about ceramic capacitors, and that mysterious thing of putting different value capacitors in parallel. Not to mention microphonics.

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By YTB

22 thoughts on “Eevblog #33 2of2 – capacitor tutorial ceramics and impedance”
  1. Avataaar/Circle Created with python_avatars MAXIMUM says:

    Vg278400 C.CE Tublr 220pf 50v and mylar on my Yamaha CD I have not heard of the first type of capacitor what type of a capacitor is C.CE Tublr please let me know

  2. Avataaar/Circle Created with python_avatars Ron Bakker says:

    A Dave Jones video under 7 min, why do feel I just teleported to an alternate universe. Had my beer ready and all, kinda feel short changed.

  3. Avataaar/Circle Created with python_avatars logiclrd says:

    I don't understand, amazing advances in technology and they just keep getting better, but the entire video is about shortcomings: they can be very sensitive to temperature, have shocking and atrocious changes in rating with temperature, are super sensitive to sound, can make your circuit noisy and are extremely brittle. So, what is this transition to them all about? Why would anyone want to transition to such a device? Are the ones they're transitioning from even worse??

  4. Avataaar/Circle Created with python_avatars Don Matejek says:

    We used to call them, "Wafer" caps!

  5. Avataaar/Circle Created with python_avatars RAShomestudio37 says:

    waouh, youtube was hard before….

  6. Avataaar/Circle Created with python_avatars Antoine de Bock says:

    Did you write a book yet?

  7. Avataaar/Circle Created with python_avatars reaper forever says:

    One of the most underrated channels I have seen

  8. Avataaar/Circle Created with python_avatars CHRISTIAN SEBA says:

    Hello I have a Sentey 750w Essential PSU in my pc gamer (i 7 / RTX2080)
    and yesterday one of this x-caps exploded ( I opened the PSU and watch a 1 of 3 x-caps exploded 0.33uf 500v X2), but the
    psu contiunued working ok, my pc start ok, next monday I will buy a new
    PSU (and maybe repair that x-caps 0.33uf later)….. the questios is?
    Can I continue playing with my pc for a few days? or will explode all my
    pc? thanks

  9. Avataaar/Circle Created with python_avatars CHRISTIAN SEBA says:

    Hello I have a Sentey 750w Essential PSU in my pc gamer (i 7 / RTX2080)
    and yesterday one of this x-caps exploded ( I opened the PSU and watch a 1 of 3 x-caps exploded 0.33uf 500v X2), but the
    psu contiunued working ok, my pc start ok, next monday I will buy a new
    PSU (and maybe repair that x-caps 0.33uf later)….. the questios is?
    Can I continue playing with my pc for a few days? or will explode all my
    pc? thanks

  10. Avataaar/Circle Created with python_avatars ventje mazzel says:

    Great video; thanks man!!!

  11. Avataaar/Circle Created with python_avatars Brian Blasius says:

    Hello, kindly do a video about feedthrough capacitors.

  12. Avataaar/Circle Created with python_avatars Crokto says:

    i was thinking "huh why dont we use ceramic caps in speaker crossovers?" and then you said microphonics. oh.

  13. Avataaar/Circle Created with python_avatars TheRandomChannel says:

    when due to microphonic effect a cap can have extra voltages, then wouldnt it be bad for the circuit? perhaps mV ranges for sensitive circuits?

  14. Avataaar/Circle Created with python_avatars John Wallace says:

    What was the name of that effect that you said effects cable?

  15. Avataaar/Circle Created with python_avatars fouzai alaa says:

    watching this in 2016 this guy is getting old !!

  16. Avataaar/Circle Created with python_avatars Power Max says:

    ceramic or film for 100KHz 100Vac? Part of a resonant circuit (high power LC oscillator as part of the drive a TV flyback transformer)

  17. Avataaar/Circle Created with python_avatars L340 says:

    Time goes by so fast!!

  18. Avataaar/Circle Created with python_avatars Rasheed Abdul-Aziz says:

    Anyone know how I can pick the 'worst' microphonic caps.. that is, I'd like to find ones that are highly inclined to produce sound, or pick it up.

  19. Avataaar/Circle Created with python_avatars es nam says:

    Thanks

  20. Avataaar/Circle Created with python_avatars Cockroach says:

    A capacitor should be operated within ~65 – 75% of their rated maximum voltage & properly polarized.

    To operate them at lower voltages, the dielectric is not placed under proper "stress" to have the capacitance they are manufactured for. Lower than that operating voltage, there is less capacitance than rated.

    You pointed out very vividly that the plates of a capacitor will move. Particularly in multi-layer capacitors. They generate physical movement which can result in micro cracks in boards. Sometimes that movement is in the audio spectrum heard by the human ear, other times ultrasonic. But there is movement which can affect the capacitance value by changing the space of the dielectric which is controlled by the applied voltage.

    Operating within the 60 – 75% range is very important for pulse forming, shaping, clampers, clippers, oscillators, or other pulse coupling, transferring or developing circuits. Grossly over maximum rated voltage component will never perform in these circuits as expected, even though the capacitance value is labeled to be a match. It does not have that capacitance value until operated within this "sweet spot" voltage range. Even for well regulated power supplies, the operating voltage should be within 60 – 75% of maximum rated voltage to stress the capacitor dielectric enough so the rated capacitance is there.

  21. Avataaar/Circle Created with python_avatars zwz • zdenek says:

    You should have mentioned the nasty residual dielectric polarization of ceramic caps. What happens is that at the range of milivolts, the apparent capacity increases a lot and the cap will keep voltage for a long time. This can freeze astable multivibrators and put a nasty offset voltage to smoothed measurement points. I always prescribe foil caps to such applications.

  22. Avataaar/Circle Created with python_avatars Dylan Reilly says:

    Studying electrical physics right now and these videos are excellent to give the equations some context.  Thank you!

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