Soldered 0805 vs 0603 vs 0402 vs 0201 vs 01005 vs 008004 today :)

[nanofrog]

Besides the price, what should one be on the look out for to detect the fakes?

Are they total crap, just the best of el-cheap'o tweezers - or are they actually usable in a pinch?
Thanks

I'd say they're usable if you're not using a microscope (FWIW, I have a 3.5x - 90x Amscope Simul-focul ). That said, the one's I'm familiar with have a wire brushed finished to them.

[schmitt trigger]

Just when one starts to believe that they cannot make the components any smaller, the manufacturers will prove you wrong.

Is there an equivalent dictum like "Moore's law" for SMT components?

[TheDane]

Just when one starts to believe that they cannot make the components any smaller, the manufacturers will prove you wrong.

Is there an equivalent dictum like "Moore's law" for SMT components?

Components are really extinct today, actually - to the naked eye, they're gone. Inside the PCB.... 
https://www.pcbway.com/blog/Engineering_Technical/Impact_of_integrated_passive_components_on_PCB_technology_development.html

http://www.electronicdesign.com/embedded/use-embedded-components-improve-pcb-performance-and-reduce-size

There's a lot of info on the internet about 'removing' passive components on the PCB. Makes reverse-engineering a whole lot harder, and performing service as well.

hmm... must be a reason why Altium can do a 3D board view inside the pcb 
- thanks Dave, oh - can you do a video on how the industry deals with 'em gone passives?

[TheDane]

There's a lot to learn.

Thanks for doing such awesome work on your video!
The switching between views made it much more interesting, and I enjoyed watching the entire thing - great work!

Coffee is no good for small high precision soldering 

Superglue is also a no good thing - at all, at least on my desk and work area.
I noticed that you splosh a lot of it on your wise in the beginning, and later on it seems you're dragging it all over the bench when you gather samples, move your tools and so on.
It takes a long time to cure, is my experience only the outer layer hardens, so whenever I am forced to (supe)glue something - I just add a drop of water on top of component/pcb, and a few secs later I suck up excess water with a q-tip - and though the glue usually turns white, it can often be handled instantly afterwards.

I have some old flux that has dripped down the side of the dispenser and the fluids evaporated. It is sticking like there's no end to it. I find it easier to scrape a tad bit off, and let it hold the component to the pcb/workarea. When the component is soldered, it usually sticks in place as the flux already is solid.
Cleaning afterwards, as you clearly show is needed - it stops electrolysis of the flux components and contaminants acting as conductors - that's my understanding of why its bubbling. Alcohol (flux) is carbon, oxygen and hydrogen bonded together, so it seems to me that it is degassing through electrolysis - and stops when you remove power.

Yes, there's a lot to learn - thanks for letting me watch your work. I hope you can use my feedback.
/Egon

Btw - it seem your logic input pin is very close to shorting to the VCC/GND pin, at the edge of the pad between your soldering via's. I know the viewing angles can be tricky, and it works.
Big round of applause - you didn't say anything about a loosing a component.     

[schmitt trigger]

Thanks TheDane for your informative links.

This technology is hybrid circuit manufacture on steroids.

Back in 1986, in the company I used to work, we incorporated a hybrid design in our product. The learning curve was steep, and during the first year of manufacturing there were lots of scrap.

What was state of the art back then, it is a trivial matter nowadays.

[ali_asadzadeh]

Do you know any Commercial PNP machines for doing 008004, I have seen myDTA top of the lines one can do till 01005, and I thought it was not safe to mass produce with them either...

[Howardlong]

The only point of the superglue is to tack the device down long enough to run a couple of wires off it, beyond that it has no raison d’etre.

You’re right, I really ought to put a small dose on a disposable bit of paper rather than the side of the vise, but you can probably see the remnants of where I’ve done it before, it doesn’t make it right though!

I just took another look under the microscope, the Schmitt trigger input looks fine as far as I can see? I’ll post a pic.

[Howardlong]

Schmitt input is ball A1, bottom left in this pic.

[TheDane]

Thanks Howardlong,

I'm referring to the pad right below the Schmitt trigger. It looks like both the wires going to the Schmitt trigger is touching this pad, but it is working - so I presume there's no short.
(The distance is very minimal, literally close to 'short' - and the flash over/spark gap voltage is likely very low.)

I miss having a good Stereo microscope, as it gives a good dept-vision/impression.

Dream-vision
Next up: 3D-Super macro videos on YouTube.
- I hope the next step in video editing software suites is 3D multicam setups for super close up nerdy video editing 

Love having electronics a hobby, as long as I don't burn or glue my fingers, eyes, etc. 

[Howardlong]

If you look closely, you can see the shadow of the wire. None of the four middle pads are used, or connected (or at least shouldn't be!).

[PixieDust]

How would you go about making a matrix of 0.65mm x 0.35mm (I think these are called 0201)? With pads underneath? From what I'm seeing:
1.) A reflow oven would be necessary
2.) Solder paste and a stencil/template

but how would go about arranging the actual 0.65mm x 0.35mm components?

[Pedro147]

I just completed the Hackaday SMD Challenge which had two 0201 components on it and I just used solder paste applied with a fine needle and hot air.

Admittedly I do have a reasonable Amscope microscope which for me is essential - old eyes syndrome 

[Rerouter]

To PixieDust

http://www.resistorguide.com/resistor-sizes-and-packages/

In the middle of the page is the land pattern.

as the land pattern allows the component to move +- 0.3mm while still connecting, I would likely use a 0.3mm courtyard lengthwise, and a 0.15mm courtyard widthwise,  (exclusion gap around the component), to prevent nearby parts forming against each other,

[PixieDust]

Ah so metric vs imperial fair enough.

My problem is that I'm trying to cram the LEDs into a matrix. They are right next to one another and their pads are underneath. I've been doing additional research and it seems like a pick and place machine would be the only option. Especially when talking about the quantities of LEDs that I'm talking about ~4000.

[Rerouter]

for a 4000 LED array, 100% i would say use a pick and place machine, the IPC footprint standards are in place to maximize yield of placed components, e.g. reducing tombstoning, and cross pad skew,

for these standards, there are still options, e.g. least, nominal and most, referring to the sizing of the pads, least having only the exact minimum amount of pad the component needs, but risks lower tolerance to small placement issues, and variation in the thickness of your solder paste layer,

e.g.
https://blogs.mentor.com/tom-hausherr/blog/2010/09/22/pcb-design-perfection-starts-in-the-cad-library-part-2/


If your confident in your manufacturers capabilities you can always push past these recommendations, but again, your yield may suffer.

[ebastler]

My problem is that I'm trying to cram the LEDs into a matrix. They are right next to one another and their pads are underneath.
[...] the quantities of LEDs that I'm talking about ~4000.

Do you really need to build this from discrete LEDs? This sounds like a use case for a small OLED or TFT display. Have you checked whether something suitable is available off the shelf? I would be prepared to accept significant design changes to avoid such a large array of discrete components -- e.g. by adapting the aspect ratio or size, or switching to a higher-than needed number of pixels.

Besides the need to make reliable electrical connections, won't you also have a requirement to align the LEDs quite precisely to make the arrangement look right when in operation? I assume this is some kind of display application. Depending on what content you want to display, the user's eye might be quite sensitive to small irregularities in LED spacing.

[PixieDust]

The device I'm trying to make hasn't been made in decades and finding one is going to be next to impossible. At the moment, I can indeed use an OLED or TFT display, but I recently found some more information on it that prompted me to start researching doing this thing the hard way. It is a visual display device but it can be broken down into smaller bits. I want to start small and then build up. I don't need to make the whole thing in one go. I want to make a tiny matrix to see if it's technically possible then move onto making the whole thing of 4000 LEDs or whatever it is.

I'm probably asking stupid questions, but you don't know until you know.

Yep, the LEDs need to be placed precisely. But close enough should do since the surface tension of the reflow process should position them correctly according to my research. They made the original device somehow after all.

[Howardlong]

More ultimate hand soldering dead bugging miniaturisation geekery, this time a blinky with the world's smallest ARM, in a 1.45mm x 1.55mm 16 ball 0.35mm pitch WLCSP Cypress CY8C4014FNI-421 Cortex M0.