PCB Manufacturing / Designing

Hello Lainons I live in a developing second world country. As of now, there are barely any PCB manufacturers in my country, so we have to import most of our PCBs from China where they are manufactured. I wish to change this by starting a PCB manufacturing business. I am an embedded systems engineer, and have experience with designing PCBs, but absolutely none with actually manufacturing them (except etching at home, but that's not scalable) I wish to talk about PCB manufacturing. Everything from making the fiberglass core, laminating with copper, to etching the circuit. Everything.

Thats a nice idea. I sit on a pile of hardware, including raw pcbs and a machine to solder on a tape. Sadly i dont really know much about hardware manufacturing in practice and my place is a mess. Yeah i have copper plates i can etch in and solder on but im not sure how to use those of what for.

>>5035 I am electrical engineer graduate and we studied this stuff in detail and let me tell you, it is a bitch and a half. The reason why China is extremely cheap is due to their cheap labor and centralization of everything so they can get cheap and easy raw materials for it all. I wish I could suggest you a book but all books I had read were written by professors on my college in my native language and there is no digital copy so... but aside from PCB manufacturing from scratch that you get into making a half-automated CNC mill and buying large PCB copper clad and enabling people in your country to buy up to two layers PCBs from you that seems like a reasonable starting point and then you can see more about it

>>5038 not an electronic myself, but example of Poland and their manufacturer Wilk Electronik making for example GOODRAM brand studff (RAM, memory cards and SSD) which that after German Quimondy get bankrupt is the only European based RAM and memory related stuff manufacturer shows in under certain conditions it's doable to even make final electronic product outside China. Not just PCBs printing/assembly service. https://en.wikipedia.org/wiki/Wilk_Elektronik

There are quite a few multilayered PCB manufacturers in Eastern Europe, some of them are old computer RnD labs from socialist times. But there is the problem: can you compete with them in delivering small batches tomorrow or with China in delivering large batches in one month?

Make it a co-operative then you don't have to manage all the time. Just work with others as equals and they will be more willing to help.

>>5035 I have been looking into a manufacturing a different type of PCBs, with the core material being very dense cardboard and the instead of copper, aluminium cladding. Aluminium is way cheaper than copper, and has similar properties just slightly lower conductivity. Its also harder to solder on, but some acid will solve that. I am really looking into using aluminium foils, the kind that are used to pack food, to make PCBs.

I don't know much about PCB fabbing correctly, but I know there are a lot of ways to do it wrong. I understand there is a lot of "secret sauce" each fab house invents on their own to avoid all manner of failure modes. Probably best to start with single or 2 layer boards and try to get the cost down. Unfortunately there is going to be a lot of competition and very thin margins due to the relatively low barrier to entry.

Does anyone have resources to share as far as proper layout designing for PCBs? Looking for book recommendations, but also good videos, courses, or anything helpful for someone wishing to create a proper circuit board layout. Bonus points if it is catered to audio circuits. I'm interested in learning the 'why-to' more than the 'how-to' As well as basic things such as optimizing placement & routing of ground planes, power bus, trace routes, etc... Some of the resources I have found are a few EEVblog videos: https://www.youtube.com/watch?v=2b1UdOmxVrw https://www.youtube.com/watch?v=VXE_dh38HjU *Both of these videos have multiple parts This video by GreatScott: https://www.youtube.com/watch?v=35YuILUlfGs Using a search engine brings up a ton of stuff ranging from not very helpful to a little more in depth, the first result seemed to have the most information: https://resources.altium.com/p/top-5-pcb-design-guidelines-every-pcb-designer-needs-know I'm hoping other lainons are more experienced than me and can share some pointers or learning resources. Specific question: Is it best to separate ground paths in an audio circuit, having them meet at a single terminal rather than using one ground plane to connect all the ground points? Apologies in advance if this doesn't make sense, I have a somewhat rudimentary understanding of electrical engineering but I'm learning more and more each week. It's been a while since I've watched the videos linked but I will review them now. I remember they definitely had enough info to get me started. I would recommend the Great Scott video first to someone who is new to this practice and wants to get started.

>>5197 When it comes to pcb layout, I'd recommend you just start making layouts for fun projects, don't worry too much about the layout, as long as you are not working with high power / high frequency stuff (way above audio range) not much can really go wrong. Just use some common sense like using thicker traces for traces that carry more power. As for stuff to get information from I would recommend downloading a program called saturnpcb. Also, some component datasheets have like reference layouts and other layout information, you can learn a lot from that. As for your ground plane question. I am pretty sure a normal ground plane will work fine in this situation, but if you got something like a high power amplifier, it might be an idea to for example have a separate ground to power the chip and a separate one as a ground reference. Just don't forget to add decoupling caps.

>>5198 Oh, and, if you have a trace that is likely to cause like interference (high power, with bursts), and traces nearby that you don't want to have a lot of noise on and stuff (not sure how else to word this in english), you might want to consider putting a bit of ground in between these traces with like, a bunch of vias to the other side to prevent crosstalk, also, you can make a sort of semi coax cable by having a trace surrounded by vias through the ground plane.

http://sam.zeloof.xyz/first-ic/ This man has made a differential amplifier IC using photolithography in a garage.

>>5233 Looks nice and I see that as a progress, but what are the limit's and what are potential uses for this right now? Could one make advanced enuff stuff to care right now or we still need some key components/things to do.

>>5256 DIY silicon is nowhere close to something like a 4004. It's going to get exponentially harder and more expensive too so don't expect this to become the new 3D printing.

>>5035 Like the others said, sounds like a meh idea, but if you want to learn more about PCB manufacturing there's a book called "Printed Circuits Handbook" by Clyde F. Coobs and it's around 1600 pages about PCB design, manufacturing, different component packages, assembly, materials, etc.

>>5256 This DIY IC is enough to make TTL logic computers like the Alto, Kenbak-1 or Datapoint 2200. This is all you need to implement a cryptographic subprocessor for hashing, symmetric and asymmetric encryption with absolutely no backdoors. >>5265 Since he has already reached <5 micron feature size, versus the 10 micron feature size of the 4004, it's only a matter of time before he makes one. There are so many modern fabrication techniques he can still use, like using germanium instead of silicon to boost clockrate, or DIY electron beam lithography to reach <7 nm.

>>5197 I recently found this thread on the kicad forums, in the replies on this forum post are some of the best advises for someone starting out with pcb design I have seen. https://forum.kicad.info/t/why-do-people-choose-to-not-use-the-auto-router/25849/48

>>5277 what clock speeds are we potentially speaking about in such cases?

>>5638 The TTL-based Xerox Alto has a clockrate of 5.88 MHz. You can actually build your own TTL-based computer that can serve HTTP and output VGA with a clockrate of 8 MHz. http://www.mycpu.eu/

>>5647 I meant for hommade lito

>>5035 Contact olimex perhaps? https://olimex.wordpress.com/about/ They are in Bulgaria. They make their own open source SBCs. They have used SMT production equipment for sale. Keep us updated though. I'm a kicad n00b but am interested in what you find.

>>5649 At least 1 Mhz, since the 1975 TTL IC computers with the same feature size are approximately that fast. The differential amplifier that Sam made has 6 transistors, compared to a TTL chip with 2 per NAND.

>>5654 7 nm 1MHz hmmm....

>>5656 It's more than fast enough for any CLI program. MyCPU at 8 Mhz can already serve HTTP pages and output to VGA.

>>5663 >It's more than fast enough for any CLI program nope, I can list many CLI programs it would be too slow for

>>5666 I hope you were not thinking of running Python or Node on a 1975 TTL-based CPU.

>>5667 well, actually I were not

I am also not an electronic tinkerer, but I know that digikey has a tool you might be interested in: https://www.digikey.com/en/resources/design-tools/pcb-builder Upload a Gerber file, make some configuration choices, and you can order from several manufacturers. Full disclosure: I work for digikey in the IT department. I have never used the service, I am just aware of it.

Try toner transfer etching if you have a laser printer, or use just make a manual PCB mill using a dremel tool.

>>6159 It doesn't make much sense to etch your own boards anymore, unless you want a 1 layer board with thick traces or you need a board immediately. I've seen 2 layer boards shipped for less than $1/pcb, and you wouldn't have to align the sides or install solder rivets.

>>6179 DIY PCB making has no lead time and does not suffer from supply chain disruption. Also no chance of botnet being secretly implanted.

>>6356 How do you exactly implant Botnet in a chipless pcb?

>>6501 not botnets, but there are techniques that involve inserting a small amount or a single logic gate that could be executed on a seemingly chipless board. Detecting certain bit patterns and changing them is possible with an extremely low part count, and could disrupt certain cryptographic schemes. I am forgetting the exact phrase to search for unfortunately. That being said, the weirdos who post on these types of sites read about this, think the black helicopters are after them, and pretend the soykafty results of toner transfer are just as good as a board house. These are incredibly sophisticated attacks that need knowledge of the software being run on the ics on the board, and have never been actually found "in the wild" afaik. To a random person getting a run of 10 boards, they absolutely do not exist. To a minor manufacturer they do not exist. To a major manufacturer, surreptitious attacks like this are less concerning than just counter-fitted compromised boards with a completely different layout being slipped into the supply chain. They're just a cool thing to read about sometimes, which is why wanna be "cyberpunks" larp as if they matter.