LCSC vs Digikey

[asmi]

Particular component is way more expensive than normal.

That's what I thought too, which is why I also offered another example of 0201 cap. I need a lot of them for FPGA decoupling, so I've been hunting for such reel at affordable for a while.

Probably caused by MLCC shortage.

I didn't notice any shortages of them on LCSC. Which makes me wonder if this "shortage" was created artificially to make suppliers rich...

[Psi]

Watch out for fakes on LCSC.
I got some SMT fuses and they were total fakes.
The solder would melt from the heat and they still had not blown.


NOTE: They were ordered and populated on a PCB by PCBWAY.
i spec'ed a LCSC part and that's what they said they used, but who knows, maybe it came from somewhere else.
Can't really be sure who to blame.

[wraper]

I didn't notice any shortages of them on LCSC. Which makes me wonder if this "shortage" was created artificially to make suppliers rich...

Many part numbers became unavailable or became priced very high, wild price fluctuations worldwide. Also average MLCC price rose a lot. Situation somewhat stabilized by now. It was not artificial, simply MLCC demand became higher than production capacity and new factories couldn't be built fast enough.
https://qz.com/1575735/a-mlcc-shortage-is-stifling-electronics-hardware-auto-makers/
At one time my favorite supplier for passives (TME) simply had no 0.1 uF 0603 capacitors left at all.

[thm_w]

Particular component is way more expensive than normal. Probably caused by MLCC shortage. For example at arrow it's 10 times cheaper compared to DK.

You are probably right. But I should have specified a bit more for the second part, DK usually has a higher "discount %" based on how many you buy, so if you buy 1 vs 100 at digikey you get a larger discount, vs LCSC the lower quantities are not quite as marked up, although it depends on the part.

It's not just Samsung. You should expect something like that when going for top notch capacitance/voltage ratings at given size.

I found others with much more respectable curves. I suspect Samsung has "optimized" for capacitance at 0V somehow (specific chemistry, etc.). Maybe other vendors are the same, I didnt compare many.

That's not really the point of this discussion, but this is exactly why you would want to pick a capacitor with highest rated voltage available in the same package.

That is generally true but not always the case, look at how fast that graph drops off. You can sometimes find better capacitors with a lower voltage spec, or with the same voltage spec and a "lower" banner spec capacitance.
Sure you can start by picking the large package size/high voltage part, but then you need to take a glance at curves IMO.

Its not the point of the discussion, but OP could be overpaying for a part that may be inferior to alternate parts, defeating the savings from LCSC.

[wraper]

BTW I would try to find the voltage/capacitance curve of that cap, there is good chance its garbage and has little capacitance above 10V or so.
I couldn't find that exact PN but here is a similar one: https://www.samsungsem.com/kr/support/product-search/mlcc/__icsFiles/afieldfile/2019/01/29/Data%20sheet_CL21A226MAYNNNE.pdf
Look how useless that thing is above 10V. This seems to be a pattern with samsung caps I looked up.

That's not really the point of this discussion, but this is exactly why you would want to pick a capacitor with highest rated voltage available in the same package.

Not really. You might notice that at the same voltage say 25V part is only barely better than 10V part but a lot more expensive. Like when @10V 10V rated cap loses 80% of capacitance but 25V cap loses 'only' 75% of capacitance. So it's best to not use extreme capacitance for the size at all (unless using them at small voltages) and just go for larger size when possible.
Here is cap from Murata, not much better than Samsung:

[asmi]

Its not the point of the discussion, but OP could be overpaying for a part that may be inferior to alternate parts, defeating the savings from LCSC.

I am the OP in this thread And I'm well aware of limitations of MLCC caps, but their advantages far outweigh disadvantages for my application.

[asmi]

Not really. You might notice that at the same voltage say 25V part is only barely better than 10V part but a lot more expensive. Like when @10V 10V rated cap loses 80% of capacitance but 25V cap loses 'only' 75% of capacitance. So it's best to not use extreme capacitance for the size at all (unless using them at small voltages) and just go for larger size when possible.
Here is cap from Murata, not much better than Samsung:

It depends on the use case. In my case the package is the most important part. All of my voltage rails are 3.3 V and lower (except for input rail, and some special cases like LCD backlighting rail), so pretty much all of them will do as far as voltage rating is concerned.

[Styno]

So far for my limited experience with LCSC, I haven't bit anything bad. I heard rumors that they don't handle parts properly (ESD, MSL, etc.), but I don't care.

I have first hand experience with this. Got a cut-tape of MSL3 led's from LCSC without proper packaging (air-tight bag with desiccant and indicator card) like you get from their Western counterparts.

FYI, it's not like I never got bad parts from Mouser. From time to time, about once per year, I got something bad from them (missing parts, superfluous parts, chipped off caps/coils, empty reels, etc.).

Mistakes are made, that's understandable up to a point. Once I received a partial reel of MSP430's from Mouser so I sent them a complaint with photo's of the empty unpeeled tape and they fixed it. Haven't had to go through this with LCSC yet

[SMTech]

We keep a vendor record for all our suppliers and all the major western suppliers to the UK, (Mouser,Digikey,RS,Farnell,Anglia,Rapid..) are well over 99% for shipping correctly. Mistakes do happen, pretty much exclusively with cut tape where the wrong device has ended up in the wrong bin somehow (all those warehouses are quite automated). We don't really use LCSC but I have looked on it a few times out of curiosity and certainly it seems pretty cheap for the common stuff. However slightly odd values or high voltage caps etc aren't stocked at all. All the western suppliers do charge a fairly large premium for the small stuff, this isn't surpsing its an expensive service to offer. They also obey their suppliers shipping and export rules (mostly one of them has got in some trouble with TI recently) , lots of industries will adjust their pricing by region. If by any chance LCSC are doing the same thing as dodgy online software sites and shipping to regions they shouldn't @ prices they shouldn't they could lose legitimate sourcing for those brands, if you're counting on that super low price, that could be painful.

LCSC are making you pay upfront, all those western companies will extend you credit, which is important if you are extending credit to your customer (std in B2B) or sticking that stuff on your shelf. The also can apply account specific discount schemes based on your volume, these can take the form of x% of all products in certain categories, or last line pricing regardless of qty ordered. In the UK RS&Farnell offer free next day shipping, your account manager can look at quotes and improve them where possible. On top of that if you have an exiting product or business they can go back to the manufacturer and get supported pricing, lower than anything they would normally offer. You can even extend your discount structure to your manufacturing partner if yours is better than theirs (maybe your little company is owned by a much bigger group)

[mrpackethead]

I find i can get another 3-5% by paying up front to so called western companys.  If you dnt' ask, you dont' get.

[SteveyG]

I found others with much more respectable curves. I suspect Samsung has "optimized" for capacitance at 0V somehow (specific chemistry, etc.). Maybe other vendors are the same, I didnt compare many.

Going off topic, but if you were interested...

[Mr. Scram]

Not in my wildest dream will i buy production components from China. Even for prototypes nothing more than resistors, since i must be 100% sure when prototyping that if i have a problem the junk parts are not in the equation. Saved me a Lot of grief over the years.

Yeah yeah you dislike anything Chinese. We know. I wonder what your house looks like without any Chinese made products.

[thm_w]

It depends on the use case. In my case the package is the most important part. All of my voltage rails are 3.3 V and lower (except for input rail, and some special cases like LCD backlighting rail), so pretty much all of them will do as far as voltage rating is concerned.

Yeah in your case its almost ideal then, 0 to 3 volts or so it hasn't dropped too much.
My complaint was coming from looking for caps for a ~20Vdc rail.

[asmi]

My complaint was coming from looking for caps for a ~20Vdc rail.

The rule I've learnt to trust is that caps' voltage rating needs to be at least twice the expected voltage of the rail. This is especially important for rails which include some cables, as you can have rather large voltage transients, and it's also valid for MLCCs for reasons mentioned above.
When you choose caps for decoupling, you pretty much need to pick as small of a package as you can, because some important cap's parasitics are pretty much set by the physical size of a cap, as opposed to any datasheet value it's got. So you would usually pick a package, and then get the highest capacitance in that package that you can get while still fitting in your budget.

[wraper]

When you choose caps for decoupling, you pretty much need to pick as small of a package as you can, because some important cap's parasitics are pretty much set by the physical size of a cap, as opposed to any datasheet value it's got. So you would usually pick a package, and then get the highest capacitance in that package that you can get while still fitting in your budget.

Unless space constrained, it's better to place in parallel small cap for low impedance at high frequencies and larger cap for bulk capacitance instead of going into extreme specs. Not only they are expensive but also less reliable due to thin dialectic and large amount of layers. Extreme capacitance MLCC going short is not rare at all.
Also for decoupling you usually don't need a lot of capacitance. Unless it's something with very high current consumption like computer CPU/GPU.

[T3sl4co1l]

FYI, ceramic capacitor voltage rating is simply what the part is tested at.  It has nothing to do with the construction, formulation or characteristics.  So, a rule of thumb like "rating twice nominal" doesn't mean anything.

Higher voltage ratings carry a guarantee of operation at that voltage, and a price premium.  The parts may well be physically identical.

Most also fail at many times the rated voltage.  I've regularly seen 6.3V to 16V parts survive over 100V.  Yes, the capacitance continues to drop at higher and higher voltages; the E(V) curve is approximately linear, interestingly enough (so, C ~ 1/sqrt(V)?).

The only consistent answer is, annoyingly: look in the datasheet, and failing that, look in the manufacturer's database.  If they don't provide a curve for the specific part, assume it's trash.  Or at least only use it at very low voltages (0-2V?).

A typical saturation threshold is 70% of nominal (-30% change).  Inductors are normally sold with a rating near here, or from -10 to -50%.  YMMV.

Tim

[ddavidebor]

Watch out for fakes on LCSC.
I got some SMT fuses and they were total fakes.
The solder would melt from the heat and they still had not blown.


NOTE: They were ordered and populated on a PCB by PCBWAY.
i spec'ed a LCSC part and that's what they said they used, but who knows, maybe it came from somewhere else.
Can't really be sure who to blame.

You can check in the box with the leftover components, the chinese version of lcsc is called 立创商城 then compare on https://www.szlcsc.com/

[asmi]

Unless space constrained, it's better to place in parallel small cap for low impedance at high frequencies and larger cap for bulk capacitance instead of going into extreme specs. Not only they are expensive but also less reliable due to thin dialectic and large amount of layers. Extreme capacitance MLCC going short is not rare at all.
Also for decoupling you usually don't need a lot of capacitance. Unless it's something with very high current consumption like computer CPU/GPU.

I'm always space-constrained as space on multilayer boards is expensive. And sometimes there is just not enough space - like between vias under BGA. Which is why I bought that reel of 0201 caps - they fit neatly between 1 mm vias without requiring any sort of technology to prevent solder from getting sucked into vias (like plugged vias, or via-in-a-pad). Since I assemble my boards manually, it doesn't matter a whole lot if I need to stuff 0402 or 0201 parts. And yes - modern SoC are requiring ever lower voltages and consume ever larger currents. For example, the Artix 100T can consume up to 7 Amps of current on Vccint rail, which is not a trivial amount.

[ebclr]

You can buy from LSSC products from Digikey, Mouser, and arrow


https://so.szlcsc.com/global.html?c=&isFormOverseas=yes

[thm_w]

You can buy from LSSC products from Digikey, Mouser, and arrow
https://so.szlcsc.com/global.html?c=&isFormOverseas=yes

So that first part as an example (GRM155R71C104KA88D), 10c ea from digikey or 12c ea from LCSC. About 2-8% markup depending on the part it seems.
Imagine buying a part, having it shipped from factory in China to digikey warehouse in USA, shipped to LCSC in China, and then shipped back again to USA for cheaper than it would be to buy it direct

I can't even think of the logistics required for this. The combining PCB + parts orders thing died off as it must have been too hard for them (would require a lot of storage space and coordination).

[mairo]

On a side note, with DK you can submit a quote for a lower price, which you can do with all other large distributors. My experience with DK is that everytime I submit a quote (regardless of the amount being $100 or $1000+) I always get a discount, most of the time it either matches the lower price from Mouser for example, or beats it by small amount. With Mouser I have never had luck getting a discount when asking for a quote (alto I have not tried hard either). With E14, is similar to DK with the difference that not all the time I get a discount, but when i do get a discount, sometimes is the lowest price of all by a good margin.

[thm_w]

On a side note, with DK you can submit a quote for a lower price, which you can do with all other large distributors. My experience with DK is that everytime I submit a quote (regardless of the amount being $100 or $1000+) I always get a discount, most of the time it either matches the lower price from Mouser for example, or beats it by small amount. With Mouser I have never had luck getting a discount when asking for a quote (alto I have not tried hard either). With E14, is similar to DK with the difference that not all the time I get a discount, but when i do get a discount, sometimes is the lowest price of all by a good margin.

Interesting, are we talking a few percent here or more, roughly? I assume you are working somewhere that has reasonable amount of business with DK.
I requested a quote from Newark/Avnet, for a piece of test gear ($1k), and they replied with the same price on the site.. So no luck there. Meanwhile transcat was 10% off, testforce 3% off.

[pk7639]

I've visited LCSC and seen their part validation process, warehouse and really cool packing carousel. I'd be confident buying from them. Perhaps I should, but I don't.. For us the convenience of a one stop shop is just worth it. When we want to buy larger volumes, we just go directly to the factories.

[ratatax]

Bought many times from LCSC and they're great.
It's as smooth as JLCPCB, i think their process is super optimized/automated to achive this kind of performance (PCBs made in 1 day, LCSC orders shipped in a few hours..)

[NorthGuy]

How about shipping? What shipping methods do they offer? Do they ship for free? Do they do DDP to Canada?