Dipped tantalums in old computers and similar devices can be also replaced with modern low ESR electrolytic or polymer capacitors. They were using tantalums back then because they didn't have anything better.

Tantalums also make fine crowbar protective circuit devices... you old timers know what I'm talking about.

used to use a lot of solid tants in our products at the time, they were quite big and heavy compared to the standard wet electrolytic ones. our units went in the cockpits of jet fighters and big turbine transports. vibration was a big thing and solid tants seem to survive it well. watching a PCB bend up and down during a resonance search test, it was not surprising how much effort went in to placement on the PCB. wrong place and it could be exit cap stage left. 🙂

ESR is also frequently dependent, I'd imagine your meter is testing somewhere from 100Hz to 100KHz ceramic caps are much better at high frequency. In the region of a few milliohms at 1Mhz and above.

I like the fact that there is still some voodoo and black magic in electronics. I'm a big Bob Pease fan (RIP) and would cackle whenever he would suggest a "whiff" of capacitance. One technique he described involved using a length of twisted pair as a capacitor, snip the length shorter until the circuit behaved as intended. I am the proud owner of a Tektronix 485, and came across a warning in one of the repair manuals not to wiggle certain transistors in their sockets, because they had been positioned deliberately during factory calibration.

All these four decades since "E over I R" & Boolean became soldered to my Pre-Frontal Lobes, figured I was the only one who used 'Ohmage'. ;-]

I've once purchased 500 MLCC 1206 capacitors with a 47uF 50V rating and I tested to have an ESR of 0.08 ohms at 1kHz! They perform really well even at 35VDC! Sadly I bought them from an Indian online store called hnhcart, and I'm not sure about the manufacturer because I can't find capacitors with such high capacitance at that voltage on major electronics retailers like DigiKey, LCSC, or Mouser! Tantalum capacitors are always expensive, and they don't have as low resistance as the MLCC often have! And I've seen most polypropylene or polyester film capacitors do have quite low ESR! I have got a 105uF huge 250VAC motor starter capacitor, which has an ESR of 0.01 ohms! Charge it up at 30VDC and short it, and it gives quite a loud bang LOL!

the standard ESR measurement is always done at 100kHz and not 1kHz. Datasheets only report ESR at 100kHz. But that's probably not the main reason to use Tantalums. Ceramics can be highly voltage dependent and thus bring a lot of nonlinearity with them that Tantalums dont. The most important thing about Tantalums is their temperature stability and moisture independence. So, no they should not be replaced with ceramics. Doing the opposite is OK but hugely expensive.

Solid Tantalums have really good electrical characteristics but, like all the different capacitor types, the application must make best use of that particular set of component tradeoffs. Solid Tantalums should NEVER be used to bypass a power supply line, unless a series resistor of at least 3 ohms per volt is used. These capacitors cannot tolerate ripple current or voltage surges. You commonly see solid tantalums used on power supply lines, and they appear to work fine but, they will short out without warning and catch on fire. Ceramic Capacitors nicely fill many applications, again when properly applied. The "K Factor" (capacitance per unit volume) must be carefully considered though. The higher the K Factor, the greater the capacitance versus package size but, with the tradeoff of higher piezo effects. This causes the capacitor to physically change shape with with applied voltage or, generate voltage when mechanical stress is applied to capacitor body. Therefore, if the ceramic capacitor is to be used in a high quality/high performance circuit, I only recommend using a dielectric constant of either NP0/C0G or X7R. Avoid at all costs, dielectrics such as Z5U.

It is always the 16V tantalum on the 12V rail that shorts out the mainboard. The 16V tantalum on the 5V rail are usually good.

Leaving a comment to show engagement for the KZfaq algos. This was a GREAT video. Well done. Bring on IMSAI Dog. :) This reminds me of Project Farms videos. Needs a spreadsheet at the end, but the hand written notes work just as well. Well done!

An early lesson for me in electronics was building up a small switching converter that specified electrolytic or tantalum decoupling capacitors. Being too clever for my own good, I decided to use some of the much smaller and more convenient ceramics I had on hand. The converter oscillated wildly because the ESR was _too low,_ and the circuit wouldn't operate correctly until I added a 1-ohm resistor in series with the capacitors. That'll teach me to read the datasheets more carefully.

My company makes hi temp downhole equipment, we have given up using tantalum long time ago, they where trouble makers getting shorted every time, we replaced them all with ceramics and standard wet capacitors for the high capacitance. I am sure there must be a specific application where tantalum performs better, but in my experience, whenever I see a tantalum cap I see failure coming soon !😂

The frequency ESR is measured at depends upon the application and if too low is going to give a false high value owing to reactance rather than internal resistance.

I hate to point this out, but the measurement is likely flawed. The ESR of the leads used is likely to be > 0.5 Ohm. Therefore you'll at best read ESR of 0.5 ohms. Was the ESR of the leads accounted for? According to the specification of the instrument for measurements < 200 Ohms requires performing the NULL operation. This is used to offset the leads ESR. Create a short on that last unused pad on the test fixture to duplicate as close as possible connect an NULL the instrument. The expected ESR (the specification for ceramic caps is very commonly 10mOhms or less, which can easily be found at a resource such as digi-key) should have given you a clue about the measurement technique.

This brings up an interesting case: the TruSDX website says that the Tayloe detector integrating capacitors (100nF each iirc) can be replaced by some (expensive) 0603 Tantalum caps for better performance. If Tantalum actually has worse ESR at those values (and likely also at the frequencies it's working with), why would Tantalum be better than ceramic in this case? Maybe it's because X7R ceramics change capacitance with voltage and temperature and have piezoelectric effects while Tantalums don't (at least as much).

I don't know how many times I've seen old teardrop tantalum's just going into full short mode and clamp a voltage bus. I know the engineers use them because of their ESR values but I've started just replacing them in old equipment when I run across them. BTW when they short they'll pump out a ton of the magic smoke. 🙂

amazing! U made it shine!

Really interesting. Thanks!

ceramic chip caps, especially higher capacities, are really very sensitive to DC bias. near their rated DC voltage, there isn't a lot left of the rated capacity. Keep that in mind when you design your circuit.

Great video.

I think there is another factor to throw into the mix - related to ESR but not quite the same. That is self-resonant frequency. That sets the upper limt of a capacitors usefulness. Even with modern electrolytics this could limit their use as decouplers in modern high-frequency logic systems.

If tantalums are anything like regular electrolytic caps, then the higher the maximum voltage rating of the cap, the lower the ESR value. (Therefore the lowest ESR you can find in an electrolytic, is a high mfd value combined with a high voltage rating (e.g. expect an ESR reading of

It would be interesting to see these capacitors on a VNA also

Ceramics are not very temperature stable either, their value is kind of a suggestion, tantalum’s are quite stable though, great for timing circuits

Both ceramic and tantalum capacitors have their own place, for high frequency applications ceramic capacitors are ideal due to their low ESR and excellent performance at high frequencies, for low frequency applications where stable operation over voltage fluctuations and temperature variations is essential tantalums should be used despite their higher ESR.

We know that by experience, Tantalums do not have a better ESR than ceramics, often worst, their main advantage is capacitance density, they are often the only way to add high capacitance in areas where space is at a premium, for example a 220uF 6V on 3528 package, good luck reaching 220uF at 6V (so, 15V on ceramic due to derating) on a 3528 footprint, it doesnt exist. However it should also be accounted that this capacitor will not have a suepr great ESR and it may cause problem for a very dynamic response (RF PA for example). The main downside of tantalums is the failure mode for polarity reversal or fault, which is short/explosion. However we nowdays use polymer tantalum capacitors (black, instead of yellow) and these do not suffer from such catastrophic failure mode. A last point to add is that there is almost no derating required with tantalum polymer caps, if the rail is 5V, it is often OK to use a 6V cap, and definitely a waste to use a 10V.

The inductance of the caps also comes into play, was hoping you would measure that as well to show that.

Good subject, considerations and video! Sort of related... I have a DE-5000. I need one of those quick-reference spreadsheets that shows the values to expect for different capacitors. There are several of these on the web. However, they seem to contain conflicting values. I would really appreciate a link to a reliable set of values. Thanks! Cheers!

Doing repairs on older equipment like the old IBM-PCs, IBM-XTs etc. my concern with Tantalum capacitors is that they tend to short. I've found many of them to be shorted and of course I don't replace them with another tantalum cap. I tend to go with a good quality higher temperature rated electrolytic.

Let’s not forget that ceramics don’t explode. Tantalum is an inferior capacitor unless you need an absolutely massive capacitor, in which case it’s superior to aluminum electrolytic. At small values, ceramic is 100% better.

Interesting I never thought of ceramic caps as being peizo electric but of course they could be. I learn something new every day :)

indeed, good video.

I agree. Tantalums were just fairly high capacity, fairly low esr, very low microphonics, in a fairly small package. That used to make them irreplaceable. That's not so true anymore. They are also volatile, so if something else more stable will do the job, by all means, use that something else.

Perhaps for low ESR you should use POSCAP tantalum capacitors! Also, the packages with the legs that come out the side and are bent around to the bottom are supposed to be superior in vibration. Recently I used larger value ceramic MLC capacitors for a multimeter DC decay timing circuit (LCD Backlight) and got way less stay-on time than I calculated. So I put an even bigger value capacitance and the stay-on time didn't get any longer, actually shorter. I deduced the MLC's had too much of a capacitance loss due to DC voltage bias. I was using random take-off SMD's, so I didn't know the chemistry of my samples. Only after switching to typical yellow tantalum capacitors did I get the long delay I was looking for.

Nice video! Where can we get the prototyping PCBs? Those are pretty slick.

The last years in our small repair business i had much more broken, i.e. shorted ceramic caps than tantalium. Not the tiny pF and nF Capacitors of course but startung at about 1-10uF i would call it a focal point of disruption... Moreover i want to remember Your cheap chinese 555 board with the ceramic capacitor beeing very sensitive / unstable to voltage change...

Type II ceramic capacitors are extremely sensitive to vibration. So much so that the same material is used in piezoceramic sensors. That in conjunction with reduction of capacitance under DC bias makes them unsuitable for many signal path applications. Type I capacitors don't have either of those issues, and they are frequently a good choice for signal path components when capacitance values less than 0.1uF are required.

Always interesting. What is the voltage rating of the SMD tantalums?

When I needed low ESR I always used paralleled ceramic disks. I've had shorting problems with dipped tants in old test equipment. I hate it when one grenades in the middle of a 3 day test regimen.

good work. two ideas: a research colleague of mine said "tantalums have no sense of humor." Next, how does capacitance and ESR change with dc bias across the capacitor? And capacitor type? Difference between tantalums and MLCC with different operating/bias dc voltage? If you don't think there is any change... And hint, it's not linear!

Thanks

I see your measurements are at 1 kHz. Also, you don’t show either aluminum or WET tantalum capacitor characteristics. Could you possibly have some old wet tantalum capacitors for comparison? Very rare nowadays, but you might find some in old PCBs. You could recognize them from their very high weight, the hermetic structure - cap welded to the can and the positive wire fed on through a glass frit, rather than some rubber or plastic. I am not sure if I have any, although I have the measuring capabilities up to 13 MHz on one instrument, up to 110 MHz on another one and theoretically up to 1 GHz on two others. But one thing I am cautious about is the ESR of the solid state electrolytics. I have had two fires in one application, 120 Hz and harmonics ripple apparently causing the overheating. In many cases they “safely!” short out, but my two fire cases ended up being just two bare wires sticking up from the board. On the other hand, I never seen failed wet tantalums.

Did you find a source for those edge SIP pins? I don't have a particular need but now I want them... :)

My LCR meter is a Der EE DE-5000. I need to make up Kelvin clips for it; I bought the clips but haven't built the adapter yet. Not sure the Keysight one at nearly $600 is a whole lot better than the DE-5000.

Nice Info

I think the concerns about microphonics comes from audio equipment like radios. A radio mounted in a car is even more of a concern. I would have been interested to see you vibrate them with a piezo while biased to compare microphonic pickup. I have heard some pretty crazy crashing noises when just tapping disk ceramics before.

Have you looked at the”polymer” tants ? Where do they fit in this scheme of things?

There are different types of ceramic capacitors, more than a few. Which type are you using?

Ceramics have lower ESR, and surprised your results were so shitty for them.

A homage to ohmage.

MYTHBUSTERS : Capacitors Episode

Which is better as an audio capacitor? ceramic vs electrolytic

Would be nice to talk about the Q factor in which ESR is part of.

Nice Info on Capacitors, Really good for New People learning Basic Electronics.. I miss telling New People to get the Old Radio Shack Mini Books on build demo electronic Projects, I still have mine that I keep on the LM555 One Shot timer IC builds I used for Displays on equipment I added on...

Leakage is something to be concerned about as well. Tantalum caps are worse than ceramics but better than eletrolytics. Also, capacitor behavior is much more complex than a static room temperature reading. Frequency, temperature, DC bias, and inductance should all be considered as well.

Have you zeroed the leads resistance? I use tantalium caps when I dont find high enough capacitance in ceramics.

Only Acid filled porous Tantalum capacitors have mOhms ESR and no inductance.

Any comments on tantalum vs. niobium caps?

Yeah but ceramics are all over place when it comes to temp, so it's worth taking your time when choosing for your application, I think we all know that and that Tants blow up so that's a worry lol ! yep caps are complicated.....cheers.

Tantalum is often over rated. ESR often seems to me to be about capacitance value & voltage rating. That 327uF cap with the low ESR might only be good to 3V with it's low ESR of 0.14 Ohms. The same value and type with a higher (often more usable voltage rating) can have much higher ESR. Another related interesting thing people say is that they switched to ceramic to avoid conflict materials and rare earth stuff but you can find those in many ceramics too. The parasitic inductance is also a fun one, people forget about it and just follow the traditions of paralleling multiple caps. I used to use 0.1uF ceramics for power supply decoupling but now I use 0603 ceramics at 10uF or 1uF instead because their internal resonance is good enough. It seems like the 0.1uF thing is a legacy of the through hole days and those wire leads really added inductance.

Great video. To my knowledge, tants were never a substitute for ceramic, instead they were a much better option than electrolytics, in terms of lifespan, filtering, and everything but size and cost. Now it's ceramics replacing tant. Which should work fine unless the circuit depends on the cap not being great...but that wouldn't be a great design, in my view.

It would have been good to see the meter being nulled at the start of the video. You did null the measurement system, right?

People like to jedge based on comparison - one having bigger is worse than one having smaller ESR. But did they chceck what is reqirement for given application? ? -According to applications one which is within limits is good , one which is outside is bad. That is what is supposed to be judged, Comparisons between two good products is useless and leads to useless decisions. For above tests I could ask basic question: is 1 Ohm good or not good. And without exact application true answer shuld be we no idea, but with practice I would say for 99,9 % cases it is fair litte. .

Mebbe level the playing field by tally RC time constant ?

How about comparing low ESR electrolytic with standard electrolytic bypassed with a ceramic cap.

A admire the effort, but I am rather skeptical that you're getting reliable ESR measurements with those clip leads.

I wondered, on your meter it showed "1 kHz" when measuring ESR. Most often ESR is measured at 50 or 100 kHz I believe, at least mine do

Ceramics have problems when voltage is aplied to it. Electrolytics dont have this. Decoupling ceramic caps loose some of its capacitance. And yes, ceramics are noisy in analog circuit.

now wet those smd ceramic capacitors, and measure them again.

Your test leads looked skinny to me, what was their resistance ?

what about max frequency

BTW I have an Imsai too :)

i really like the content of this video but the camera movements are really unfortunate. why not use 2 cameras, one points to the meter, the other to what you’re measuring? i appreciate your content a lot.

I rather wanna see bad ESR or microphonic effect, then get my house, lab or garage burn down....

My question would be do they Sound better??

There are much better tantalum capacitors on different pc video cards and motherboards. They have about miliohms and capacity 220-470 uF

You have measured like 1 ohm ESR for those smd ceramic caps? There must be some problem with measurement method.

You need network analyser vs frequency, , that Fluke don't tell you the true 👋👋👋👋👋👋👋👋👋👋👋👋👋

Cap Bait. Lol. Let the comment wars begin. 😂

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Great video, but would have been more scientific to use the same value capacitor on something like a 2.2uf capacitor of each type, That and maybe having a higher and lower voltage rated cap to directly show the effects. Most testers and manufacturers I believe report specs at 100khz,, so those numbers might be more apples to apples for those doing their own tests at home. The "magic" capacitors I always thought were organic polymer, but that's probably overkill in most applications

Tantalum soldered on nice polished aluminum electronic board on military airplaine, like a superhero, resistant on most factors, vibration, humidity, etc, etc..but give him some volts of high frequency sharp sinus tone, and tantalum will explode after 10 seconds :)...inner inductance or reactans, dont blame tantalums, blame purpose and conditions.