Laga soo bilaabo wareegyada tusaalaha ee looxyada roodhida si loo naqshadeeyo annaga guddiga wareegsan oo daabacan (PCBS), it was like getting off the training wheels. There’s a lot to learn about this process, so let’s get started. Naqshadeynta PCB waxaa lagu fuliyaa habka injineernimada korontada (EE). EE wuxuu abuuraa “maskaxda” sida qalabyadu u shaqeeyaan. Without electronics, you’re left with little more than a pile of metal and plastic.

Things to know before starting PCB design: 1. PCB size – this depends on your product size (or case size). Cabbirka badeecada waxaa lagu qeexaa inta lagu jiro habka naqshadeynta injineernimada elektaroonigga ah. You can watch a video about it here. 2. Lakabyada PCB – Lakabyada badan, ayaa ka sii murugsan SAMAYNTA PCB. (Xusuusin: Xitaa PCB-ka hal-lakab ah wuxuu noqon karaa PCB adag, laakiin halkan waxaan ka hadlaynaa kakanaanta samaynta PCB. Lakabyada badan ee PCB -ga leeyahay, aad bay qaali u tahay in la sameeyo.)

Layer 2 is usually used for simple toy products

Badeecadaha la xiriira caadiyan waxay leeyihiin 4 lakab

Typically used for floors 6 to 8 of a smartphone or smartwatch.

3. Your PCB manufacturer’s requirements. Be sure to read the guidelines for rhythm, trace size, power isolation, and file naming before you start designing.

Macluumaadka aad u baahan tahay inaad siiso soo -saareyaasha PCB:

Tirada lakabyada (tusaale. 2, 4, 6, iwm.)

Qalabka (FR-2 (warqadda suufka phenolic), FR-3 (warqad suuf iyo epoxy), FR-4 (fiber galaas iyo epoxy… Etc.)

Thickness (0.5 mm, 1.0 mm… Etc.)

Color (red, black, green… Etc.)

Daaweynta dusha sare (ENIG (nikkel kiimiko/dahaadinta dahabka), DIG (bakhtiinta dahabka tooska ah), OSP (waxyaabaha ilaaliya dabiiciga ah, iwm.)

Copper weight (1 oz (35 microns), 2 oz (70 microns), 0.5 oz (18 microns)… Etc.)

Faylka Gerber

PCB design process:

Naqshadeynta wareegga

For this step, you need to create the schematic. This is a document, like a blueprint, that describes how components relate to each other and work together. To create the schematic file, you will need a software tool. We like Quadcept because it is optimized for designing PCBS for manufacturing (for example, you can export a Bill of Material (BoM) directly from the tool) and is cloud-based, so it can be easily used anywhere. (They also offer a free community version of the tool for manufacturers and students.)

There are many other options you can choose from:

Altium

ExpressPCB

Aaladda soo noqnoqoshada

KiCad

Cadence allegro

derin

Naqshadeynta kumbuyuutarka caawisa

DipTrace

After you install the selected tools, you need to obtain the component specifications for each selected component. They can often be found on the supplier’s website. Faylka tusaalaha ah ayaa kaa caawin doona inaad sawirto qaab -dhismeedka. This component becomes available in the database when you upload the model to the software tool. Then, all you have to do is follow the data manual and connect the wire to each pin in the component. (Xusuusin: faahfaahinta habka naqshadeynta waxay ku xirnaan doontaa aaladda software -ka la doortay).

Each schematic symbol needs to have an associated PCB space area to define the physical dimensions of the component and the location of the through holes on the brazing pad or PCB. You should have selected the components (or are now selecting them), and we describe this process in the EE Design Process video (see video).

Example diagram

A good schematic is really important, as it will be used as a reference document during debugging and is a good communication tool with other engineers. Intaa waxaa dheer, soo -saaraha ayaa tijaabin kara aaladda iyada oo loo marayo dhibcaha imtixaanka ee dukumintigan.

PCB layout + Gerber file

To design the PCB layout and create Gerber files, you can use the same software tools we mentioned in circuit design. Si ka duwan qaab -dhismeedka, qaab -dhismeedka PCB wuxuu u xilsaaraa qaybaha dhabta ah meelaha saxda ah ee PCB -ga wuxuuna tusayaa raadadka isku xira qayb kasta oo u dhexeeya lakabyada PCB. As mentioned at the beginning of this article, the more layers, the more complex the manufacturing required, and the higher the cost.

Divide the PCB into logical parts based on functions (e.g. power supply, audio output, etc.). Then, be sure to group the components of each section into the same area. Sidan, waxaad ku hayn kartaa raadinta tabinta oo gaaban waxaadna yareyn kartaa buuqa iyo faragelinta.

Xiriirka adeegsadaha (UI) ayaa sidoo kale u baahan in maskaxda lagu hayo marka la dejinayo PCB. Qeybaha sida jaakadaha maqalka, isku xirayaasha, leedyada, iwm waxay u baahan yihiin in la hagaajiyo si loo gaaro waayo -aragnimada isticmaalaha ugu fiican.

Once the layout is designed, a Gerber file is generated. Soo -saarahaaga PCBA ayaa isticmaali doona faylkan. There are many companies that offer these services, and from HWTrek’s expert library we recommend Kingbrother, NexPCB, and HQPCB.

Tusaalaha Gerber faylasha

Meelaynta qaybaha PCB -ga aad bay muhiim u tahay. Some components can interfere with each other and cause unexpected behavior. For example, if you have both Bluetooth and Wi-Fi modules, they have the same 2.4ghz bandwidth and can interfere with each other if incorrectly placed.

PCB production

When you send the Gerber file to the PCB manufacturer, they can print the board. Tani waxay saldhig u noqon doontaa in la sii dhiso aasaaska loogu darayo qaybaha PCB -ga iyo soo saaridda PCBA (shirka guddiga wareegga daabacan).

Unassembled PCBS

PCBA (Assembly)

Qalabka diyaarinta

Waqtigan xaadirka ah ee naqshaddaada EE, waa inaad dooratay qaybaha. You can ask the PCBA manufacturer to order the required components for you, or do it yourself if you choose a supplier. Arimaha u baahan feejignaan

Lead time: As these components come from different suppliers, keep the lead time in mind. For some components, it can take up to 8-16 weeks.

Packaging: Order components from reels that are automatically picked up by SMT machines instead of packaging them individually.

Minimum order quantity: Check the minimum order quantity of the component. Haddii aad iibsato wax ka yar kan ugu yar, hubso in qaybaha la doortay ay kayd ku jiraan. For small batches (up to 50), you can order online from DigiKey or Mouser. Tiro badan, fadlan talo ka raadi soo -saarahaaga.

Loss: Order 10% more to cover loss (not for expensive components)

Install components on the PCB

There are two main ways to place components on a PCB surface:

Through-holes (through-holes) are manual methods of assembling assemblies with wires into holes on the surface of a PCB. It is also commonly known as DIP or dual in-line packaging process. (See SMT in progress in this video)

SMT (teknolojiyadda buurta dusheeda) waa habka ugu badan ee loo adeegsado wax soo saarka ballaaran. It is done by fast, accurate SMT machines that save you time, money and avoid human error.

Waxyaabaha la xusuusto:

Your component type number must not exceed the number of reels that the manufacturer’s SMT machine can support.

Optimize and consolidate your components so that only one SMT runs.

Check manufacturer supported footprint pad sizes. Otherwise, the SMT machine will not install components correctly.

Some larger components cannot be installed by machine and still require manual through-hole work. Therefore, both technologies can be used on the same board.

Any components you need to manually add via the through-hole method add to the manufacturing cost.

Reflow soldering

Reflow soldering is the process of making components “stick” to the PCB. PCBA waxay ku kululaysaa guddiga wareegga iyada oo loo marayo foorno dib -u -celin ama laambad infrared ah ilaa albuhu dhalaalayo, oo si joogto ah ugu dhejinayo qaybta guddiga wareegga.

The trickiest part here is not to overheat or damage the components, because the thermal characteristics of each package are different. Soo -saare PCBA oo la isku halleyn karo ayaa mas’uul ka noqon doona habsocodkan, oo waxa kaliya oo aad u baahan tahay inaad samayso waa inaad siiso tilmaamaha qaybaha.

Habka reflux.

Other welding methods:

Wave soldering is mainly used for manually added components by the through-hole method. In this case, your PCBA will first go through the reflow welding furnace, and then manually add other components after it will go through the wave soldering machine.

Alxanka birta waxaa loo isticmaali karaa xaalado gaar ah, laakiin looma adeegsan karo wax -soo -saar ballaaran.

Baaritaanka iyo tayada tayada

Tallaabadan, shaybaarka PCBA waa la tijaabiyaa si loo hubiyo tayada. Khaladaadka caadiga ah ayaa ah: wareegyada gaagaaban ee qaybaha kala go’ay, qaybaha aan si khaldan loo qeexin iyo qaybo ka mid ah wareegga oo aan la xiriirin. Tijaabooyinka ugu badan:

ICT (Imtixaanka onlaynka ah). When designing a PCB, some test points are usually reserved for debugging, programming, and other purposes. Mashiinka ICT -ga wuxuu u adeegsan doonaa dhibcahaas imtixaannada wareegga furan/gaaban wuxuuna hubin doonaa in qiyamka qaybaha aan tooska ahayn (resistors, inductors, capacitors) ay ku jiraan baaxadda qeexidda.

AOI (Kormeerka indhaha ee otomaatiga ah). Manufacturers use a “gold sample” (reference PCBA) to compare with other samples. Imtixaankan, abuuraha qalabka wuxuu u baahan doonaa inuu siinayo tilmaamaha iyo dulqaadka soo -saaraha si uu u dejiyo cabbirrada.

Raajo. The PCBA manufacturer will use X-rays to check the welding conditions of the BGA (ball Grid Array) components. Fiiri fiidyowgan ka eeg baaritaanka Raajada.