EEVblog #33 2of2 - Capacitor Tutorial (Ceramics and impedance)

[@azdinator]

This guy is great. He's passionate and loves his job. We need some guys like him in France.

[@Afrotechmods]

5 stars for teaching me about the microphonic effect! I am guessing this effect is more of a problem with very low capacitance values like a few pF?

[@reaperforever8478]

One of the most underrated channels I have seen

[@dylanreilly6888]

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

[@zwz.zdenek]

Not sure about your career plans, but you probably should have been into electronics before enrolling in that school. I mean, those things he explains are pretty basic.

[@kirsten0233]

ZdenekJindra That was kind of rude.

[@zwz.zdenek]

MissChrisDandy I don't see anything rude there. It's just an honest opinion on the state of affairs. One should already be good and talented before trying to finish it successfully with a degree.

[@maboroshi1986]

ZdenekJindra you know you can be into something as a hobby or interest and when you go for formal education into that thing find that some stuff goes over your head. i was the same when i started studying chemistry in college.

[@Cockroach2008]

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.

[@Sammus7t]

Good tip. Thank you for sharing.

[@EEVblog]

@CoolDudeClem Yes, in cables it's called the Triboelectric effect.

[@EEVblog]

It can, yes. Although products like that are usually vibration tested at the design stage. They have to meet certain minimum requirements in order to be transported by road and air to the end user without being damaged for starters. There are industry standards for this.

[@EEVblog]

@rellimxelabolly A capacitor has small amounts of inductance and resistance in it also, hence the shape of the curve.

[@ronbakker1300]

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.

[@Olwe90]

Keep it up mate. Even though I'm doing 2nd year mechanical engineering and taking digital circuitry, always learn new things from your video blogs.

[@CoolDudeClem]

I have not heard of microphonics in capacitors before, but I have experienced it with cables. Quite a few times when handling a cable connected to a piece of audio equipment, I could hear the sound of the cable being moved comming out though the speakers, as if there was a microphone connected to it whitch of course there wasn't!

[@Tutoelectro1]

Thanks again Dave, always great stuff!

[@zwz.zdenek]

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.

[@Satchmoeddie]

When you stick you amplifier chassis in a combo guitar amp with 4 10 inch loudspeakers in the same cabinet it brings out microphonics in components big time. It is still kinda rare, but these are what brings out the worst. You mentioned Monster Cable liking to sue. This is rampant in guitar amp circles. One company was found to have used designs from 1950s magazines. People they had sued were lining up to counter-sue. Some people were sued out of business. They "were" the Monster of guitar amps.

[@jan.tichavsky]

Class 2 can have large capacitance changes not just over temperature but even over different voltages across the cap so watch out, it gets worse with larger values. At work we have some boards with 10n and 22n NP0 caps but such large values are expensive.

[@planexzeropoint]

like the bit at the end with the wave form as well, be cool if you could set up a phi gap ratio, the mind truly boggles.

[@ingtasco]

Hello I am from COLOMBIA love it.. I am learning much with these videos.. Thank Dave... and Thank them for the subtitulos.. My English is very bad.

[@Satchmoeddie]

The Z grades are worse than the old FP caps. I usually only use a .01 @ 250 VAC to ground from a neutral on my hand made tube amps, or repairs or removal of the two prong "death caps" on the mains cord. Ceramic caps have gotten better since the 60s-70s. My LCR will graph all the Z, Q etc from 10Hz to 20KHz. Ceramic for audio has a bright tone compared to polyester. or polypropylene. Guys went gaga over Tantalum when they first came out, but I think price was the influence.I Loved this segment!

[@leaoaugusto]

Time goes by so fast!!

[@Sammus7t]

Seems to move faster every year.

[@RobertGallop]

Love it, more info like this on components, any and all!

[@deagle94]

it means it cannot handle more than x volts on its + terminal. you cant hook up a 9v battery to a 5v rated capacitor, it would explode. what you need is twise as much as the suppy voltage, so 9v x2 = 18v rated capacitors are needed. this is because of possible peak voltage ripple.

[@thedivinityman]

I can a car ampliphier that played the music when it was not hooked up to the speaakers, I wonder if it was due to the microphonic phenonem

[@morlanius]

Sometimes in car amps the step up transformer is causing a magnetic flux with the casing causing it to vibrate. That is likely what is causing you to hear it, the effect with the caps is very small.

[@LoranDavis]

Yeah that's way cool about the "microphonic" aspect of these things. I think I've noticed that when I dropped our landline telephone and heard a little ring in the receiver. I could hear it when I whacked the phone off the table too LOL!!

[@canlelola]

You just gave me an idea for a project, to make a Transistor Tester with ESR.

[@SqueeDee]

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.

[@RannoRannikmaa]

like everything else more you know more complicated it gets :D

[@Solveprobs]

How is the decoupling capacitor value selected?

[@38911bytefree]

Brilliant Dave.

[@pasihein]

Dave, you rule. Great videos, thanks man!

[@brianblasius]

Hello, kindly do a video about feedthrough capacitors.

[@therandomchannel9226]

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?

[@power-max]

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

[@logiclrd]

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??

[@Iseekoutthetruth]

what do you know about Nikola Tesla electric car the arrow, they say it had 1 car battery that could be driven on everyday and that he used a super capacitor and had a 6 foot antenna that stuck up in the air in the back of his car. could the antenna have been a micro phonic capacitor?

[@maximum7904]

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

[@ksjoberg]

Y5V tolerance isn't -82%, it's +82%! Though it's still -20%ish...

[@Gameboygenius]

Microphonics? Don't tell the audiophools, mate. ;)

[@DirtyAssa]

That's super great! I'm looking for impedance things for audio electric! I'm no educated amateur searching things here! I play guitar and I'm looking for all the people for make many shows with me, some money too! I wanted to build and repair some audio electric for own use but also for any purpose! It's hard to find people interested to do something but I won't give up! Thanks very much for that video! I subscribe and add that to my playlist! I'll try the microphonic of capacitors soon! Thumbs!

[@TheThievingBeggars]

I like this guy! Good video, very informative! Thanks for this!

[@davidbball13]

AHHHH i friggin love your videos

[@planexzeropoint]

hey dave, what's your thoughts on using barium titanate instead of ceramics?

[@fouzaialaa7962]

watching this in 2016 this guy is getting old !!

[@Sammus7t]

Happens to the best of us. :\

[@johnwallace1012]

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

[@rustynuckles3662]

How do I determine the microfarad rating of a round ceramic capacitor that came out of an Xbox 360 power brick. I see the micro farad symbol but it is followed by 08 11 The markings are as follows: MOV 24 1KD10 (micro farad symbol) backwards R, italicized U,08 11 So it's RU08 11

[@chubsnellie]

so using them in series can smooth out the circuit?

[@christianseba9811]

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

[@lucaspremuda4403]

2:03 with English subtitles

[@ventjemazzel8822]

Great video; thanks man!!!

[@lucasmontec]

Well, after all this... what is the best capacitor?

[@PvPbomber009]

English captions are legendary on this one :DDDDD

[@Anteino]

Did you write a book yet?

[@Crokto]

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

[@sharymens8187]

Thank you!

[@vitalsfading]

vacuum tubes baby, nothing like a micro phonic vacuum tube in an amp

[@lesterliston27]

all I can say is WOW!!!!!!!!

[@MrDoneboy]

We used to call them, "Wafer" caps!

[@gonXay]

1:41 "shocking" It literally is

[@LaraSchilling]

3:00 OMG AWESOME :D

[@LainInnocenti]

thank you, keep it up please.

[@esnam6557]

Thanks

[@CyrusBrinkworthRAS]

waouh, youtube was hard before....

[@DarkMatterX1]

How the hell does Dave get dislikes? Someone's smoking the heavy dope methinks.

[@stivep1]

Please read my PM I have send to you with material related to this video and new subject to discuss Wesley

[@christianseba9811]

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