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Come in through-hole components your time is up!
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tooki:

--- Quote from: eti on December 28, 2021, 03:32:56 am ---Since the asker is unsure, let me ask you this - have you considered how many devices are used by the military, of which GIGANTIC numbers are deployed, which are so vastly expensive that they’re expected to last (and be repairable) for decades - think that they need to be serviced, and the components needs to be VERY firmly attached, but which also need to be serviced in locations that can’t always be lifted out like an operating theatre (IE, on the battleground) and how many are legacy industrial devices which continue in manufacture as nothing “better” is needed, and their systems simply depend on things (“if it ain’t broke, don’t ‘fix’ it”)

...

Defence contracts are funded by bottomless pockets, and if they say THT stays, nothing else matters - that’s the final word on it, and since lots of our technology descends from military research… well… that’s all there is to it.

--- End quote ---
You are suggesting that the military uses THT parts because of reliability. As a blanket statement, that is a complete and utter fabrication.

Yes, the military (and aerospace) generally demands high reliability, and often demands extremely long repairability and parts availability. But that simply ensures old component types will remain available (be it by continued manufacturing or by suppliers stockpiling parts). It doesn't say anything at all about whether or not an old component type is superior to a newer type.

A THT component need not be more reliable than an SMD equivalent. For example, SMD components often do better at vibration resilience.

You also imply that THT is more serviceable than SMD, and that, too, is only true to an extent. Each technology has its own challenges, and with the right tools, service is a routine thing. With the proper tools, an SMD component is often easier to replace than the THT version. I think people often think SMD is "harder" to work with, because they're working with tools fundamentally designed for THT, so yeah, it's gonna suck. But if you get tools designed for SMD, it's easy. (And those tools, in turn, suck at working with THT parts.)

And may I remind you that the military (and aerospace) was among the very first users of SMD parts? They've been using them since the 1960s, right alongside THT components.
Microdoser:
I use through hole when doing initial prototypes. The parts are larger, you can see what they are without using a scope, and you can disconnect them and reconnect them in various configurations more easily.

You can also shove them into a breadboard ;)

For later designs, I use as much SMD stuff as I can. I still like to have things like ethernet ports through hole, but this is only because you don't save any space because the connector itself is massive, and for fixing strength. Smaller connectors like smaller USB connectors can go SMD.

You can just do more with less space when you go SMD IMO
nctnico:
I strongly prefer through hole for connectors as well for the mechanical strength.
HobGoblyn:

--- Quote from: nctnico on December 28, 2021, 01:47:25 pm ---
--- Quote from: PixieDust on December 27, 2021, 03:13:06 pm ---Sorry for posting in an old thread, I think the topic is still pertinent. I was wondering how you prototype on breadboards if TH is dead? How do you prototype with TH?

--- End quote ---
Who would use breadboards anyway? The major thing I recall from breadboard are flaky contacts.

--- End quote ---

Someone starting out in electronics, learning from books, YouTube etc, being able to quickly change parts/values etc on a breadboard, I personally think when starting out, it’s a necessity.

Cerebus:

--- Quote from: tooki on December 28, 2021, 02:26:56 pm ---And may I remind you that the military (and aerospace) was among the very first users of SMD parts? They've been using them since the 1960s, right alongside THT components.

--- End quote ---

That must be rubbish, I mean you couldn't use nascent surface mount technology, stick it in a dirty great Saturn V rocket and launch it at the moon, could you?


Saturn V Launch Vehicle Digital Computer board.

Oh. Oh yes you could.  :)

Modern SMD chips are much more reliable than THT chips. I've been using tiny little DHVQFN16 packages for boring old 74 series logic recently.



These both literally contain the same silicon die. One is a a lot cheaper and takes up a lot less room on the board.

It would be pointless to do the "deciding which is left as an exercise for the student" bit.  :)

Nexperia (nee NXP) have this to say about the SMD packages:


--- Quote from: Nexperia Logic Handbook ---Contact area vs. chip area: the key to mechanical strength

As mentioned in the previous section, leadless packages offer superior durability compared to leaded packages. The primary reason for this is quite simple: solder provides the mechanical connection between a device and the PCB, and packages that have a higher ratio of contact area to package area will have more solder relative to the size of the package/IC.

Leadless packages have far higher contact-area-to-chip-area ratio than the leaded parts. Furthermore, testing conducted by Nexperia has confirmed that leadless components can surpass leaded components in their ability to withstand both pull force and shear force.

--- End quote ---
(Emphasis mine)

It's intuitive. A package that weighs milligrams attached to a board by solder over almost 50% of its area versus a package that weighs perhaps 100x as much cantilevered off the board by lots of flexible metal pins that are subject to vibration induced fatigue (remember how quickly copper work hardens and breaks, I bet we've all deliberately snapped a copper wire in a few seconds by repeated bending).
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