Konprann pwosesis asanble tablo PCB epi santi w cham vèt PCB

An tèm de teknoloji modèn, mond lan ap grandi nan yon vitès trè vit, ak enfliyans li ka fasilman antre nan jwe nan lavi chak jou nou an. The way we live has changed dramatically and this technological advance has led to many advanced devices that we didn’t even think of 10 years ago. Nwayo a nan aparèy sa yo se jeni elektrik, ak nwayo a se an lèt detache sikwi tablo (PCB).

Yon PCB anjeneral vèt e li se yon kò rijid ak divès eleman elektwonik sou li. These components are welded to the PCB in a process called “PCB assembly” or PCBA. PCB la konsiste de yon substra ki fèt ak vèr, kouch kòb kwiv mete ki fè tras la, twou ki fè moute eleman an, ak kouch ki ka enteryè ak ekstèn. Nan RayPCB, nou ka bay jiska 1-36 kouch pou milti-kouch Pwototip ak 1-10 kouch pou lo miltip nan PCB pou pwodiksyon volim. For single-sided and double-sided PCBS, an outer layer exists but no inner layer.

ipcb

The substrate and components are insulated with solder film and held together with epoxy resin.The welding mask can be green, blue or red, as is common in PCB colors. Mask la soude pral pèmèt eleman an pou fè pou evite kout kous nan tras la oswa lòt konpozan.

Tras Copper yo te itilize yo transfere siyal elektwonik soti nan yon pwen a yon lòt sou yon PCB. These signals can be high-speed digital signals or discrete analog signals. Fil sa yo ka fè epè yo nan lòd yo bay pouvwa / pouvwa pou ekipman pou pouvwa eleman.

Nan pifò PCBS ki bay gwo vòltaj oswa aktyèl, gen yon avyon baz apa. Components on the top layer are connected to the internal GND plane or internal signal layer via “Vias”.

Konpozan yo reyini sou PCB la pou pèmèt PCB la opere jan sa fèt. The most important thing is PCB function. Menm si ti rezistans SMT yo pa mete kòrèkteman, oswa menm si ti tras yo koupe nan PCB la, PCB la ka pa mache. Se poutèt sa, li enpòtan yo rasanble eleman nan yon fason apwopriye. PCB la lè rasanble konpozan yo rele PCBA oswa PCB asanble.

Tou depan de espesifikasyon ki dekri nan kliyan an oswa itilizatè, fonksyon an nan PCB la ka konplèks oswa senp. PCB size also varies according to requirements.

The PCB assembly process has both automatic and manual processes, which we will discuss.

Kouch PCB ak konsepsyon

Kòm mansyone pi wo a, gen kouch siyal miltip ant kouch ekstèn yo. Now we will discuss the types of outer layers and functions.

Understand PCB board assembly process and feel the green charm of PCBD

1 – Substrate: Sa a se yon plak rijid te fè nan FR-4 materyèl ki te sou eleman yo “plen” oswa soude. Sa a bay frigidité pou PCB la.

2- Copper layer: Thin copper foil is applied to the top and bottom of the PCB to make the top and bottom copper trace.

3- Mas soudi: Li aplike nan kouch anwo ak anba PCB la. This is used to create non-conducting areas of the PCB and insulate the copper traces from each other to protect against short circuits. Mask la soude tou evite soude pati vle ak asire ke soude antre nan zòn nan pou soude, tankou twou ak kousinen. These holes connect the THT component to the PCB while the PAD is used to hold the SMT component.

4- Screen: The white labels we see on PCBS for component codes, such as R1, C1 or some description on PCBS or company logos, are all made of screen layers. Kouch ekran an bay enfòmasyon enpòtan sou PCB la.

There are 3 types of PCBS according to the substrate classification

1- Rigid PCB:

PCB yo pi fò nan aparèy PCB nou wè nan divès kalite PCB. Sa yo se difisil, rijid ak solid PCBS, ak epesè diferan. The main material is fiberglass or simple “FR4”. FR4 kanpe pou “flanm dife-4”. Karakteristik pwòp tèt ou-etenn nan FR-4 a fè li itil pou itilize nan anpil difisil-nwayo endistriyèl aparèy elektwonik. The FR-4 has thin layers of copper foil on both sides, also known as copper-clad laminates. Fr-4 laminates kwiv rekouvèr yo pwensipalman itilize nan anplifikatè pouvwa, oblije chanje ekipman pou pouvwa mòd, chofè servo motè, elatriye. Nan lòt men an, yon lòt substrat PCB rijid souvan itilize nan aparèy nan kay la ak IT pwodwi yo rele papye fenol PCB. Yo se limyè, dansite ki ba, bon mache ak fasil kout pyen. Kalkilatris, klavye ak sourit yo se kèk nan aplikasyon li yo.

2- Flexible PCB:

Made from substrate materials such as Kapton, flexible PCBS can withstand very high temperatures while being as thick as 0.005 inches. It can be easily bent and used in connectors for wearable electronics, LCD monitors or laptops, keyboards and cameras, etc.

3-metal core PCB:

In addition, another PCB substrate can be used like aluminum, which is very efficient for cooling.Sa yo kalite PCBS ka itilize pou aplikasyon pou ki mande pou eleman tèmik tankou poul pouvwa segondè, dyod lazè, elatriye.

Installation technology type:

SMT: SMT kanpe pou “sifas mòn teknoloji”. Konpozan SMT yo piti anpil nan gwosè ak vini nan pakè divès kalite tankou 0402,0603 1608 pou rezistans ak kondansateur. Menm jan an tou, pou sik sik entegre, nou gen SOIC, TSSOP, QFP ak BGA.

SMT asanble trè difisil pou men moun epi li ka yon pwosesis pwosesis tan, kidonk li se sitou fè pa otomatik pickup ak plasman robo.

THT: THT kanpe pou teknoloji twou. Components with leads and wires, such as resistors, capacitors, inductors, PDIP ics, transformers, transistors, IGBT, MOSFET, etc.

The components must be inserted on one side of the PCB on one component and pulled by the leg on the other side, cut the leg and welded. THT assembly is usually done by hand welding and is relatively easy.

Asanble pwosesis kondisyon:

Prior to the actual PCB fabrication and PCB assembly process, the manufacturer checks the PCB for any defects or errors in the PCB that could cause the failure. This process is called the Manufacturing design (DFM) process. Konpayi fabrikasyon yo dwe fè etap debaz DFM sa yo pou asire yon PCB andomaje.

1- Component layout considerations: Through-holes must be checked for components with polarity. Like electrolytic capacitors must be checked polarity, diode anode and cathode polarity check, SMT tantalum capacitor polarity check. IC dan / tèt direksyon yo dwe tcheke.

Eleman ki mande koule chalè a ta dwe gen ase espas pou akomode lòt eleman pou lavabo chalè a pa manyen.

2-Hole and through-hole spacing:

The spacing between holes and between holes and traces should be checked. Pad ak nan twou pa dwe sipèpoze.

3- Brazing pad, thickness, line width shall be taken into account.

By performing DFM inspections, manufacturers can easily reduce manufacturing costs by reducing the number of scrap panels. This will help in fast steering by avoiding DFM level failures. At RayPCB, we provide DFM and DFT inspection in circuit assembly and prototyping. Nan RayPCB, nou itilize ekipman OEM eta-of-atizay la bay sèvis OEM PCB, vag soude, tès kat PCB ak asanble SMT.

PCB Asanble (PCBA) etap-pa-etap pwosesis:

Etap 1: Aplike kole soude lè l sèvi avèk modèl

First, we apply solder paste to the area of the PCB that fits the component. This is done by applying solder paste to the stainless steel template. Modèl la ak PCB yo kenbe ansanm pa yon aparèy mekanik, epi kole soude a aplike respire nan tout ouvèti nan tablo a nan yon aplikatè. Apply solder paste evenly with applicator. Se poutèt sa, yo dwe itilize keratin soude apwopriye nan aplikatè a. Lè yo aplike a aplike, keratin nan ap rete nan zòn nan vle nan PCB la. Grey soude keratin 96.5% te fè nan fèblan, ki gen 3% ajan ak 0.5% kwiv, plon gratis. After heating in Step 3, the solder paste will melt and form a strong bond.

Step 2: Automatic placement of components:

Dezyèm etap la nan PCBA se otomatikman mete eleman SMT yo sou PCB la. Sa a se fè lè l sèvi avèk yon chwazi ak kote robo. Nan nivo konsepsyon an, designer a kreye yon dosye epi li bay robo otomatik la. Dosye sa a gen pre-pwograme X, Y kowòdone nan chak eleman yo itilize nan PCB la epi idantifye kote tout eleman yo. Using this information, the robot only needs to place the SMD device accurately on the board. The pick and place robot will pick up components from its vacuum fixture and place them accurately on the solder paste.

Anvan avenman robotik pickup ak plasman machin, teknisyen ta ranmase konpozan lè l sèvi avèk Pensèt epi mete yo sou PCB la pa ak anpil atansyon gade nan kote a ak evite nenpòt ki souke men yo. This results in high levels of fatigue and poor vision for technicians, and leads to a slow PCB assembly process for SMT parts. Se konsa, potansyèl pou erè a wo.

Kòm teknoloji échéance, otomatik robo ki ranmase epi mete konpozan diminye kantite travay la nan teknisyen, pèmèt plasman rapid ak egzat eleman. Robo sa yo ka travay 24/7 san fatig.

Etap 3: Reflow soude

The third step after setting up the elements and applying the solder paste is reflux welding. Reflow welding is the process of placing the PCB on a conveyor belt with components. The conveyor then moves the PCB and components into a large oven, which produces a temperature of 250 o C. Tanperati a ase pou fonn soude a. Soude a fonn Lè sa a, kenbe eleman nan PCB la ak fòme jwenti a. After high temperature treatment, the PCB enters the cooler. These coolers then solidify the solder joints in a controlled manner. Sa a pral etabli yon koneksyon pèmanan ant eleman SMT a ak PCB la. Nan ka yon PCB doub-sided, jan sa dekri anwo a, bò PCB ki gen mwens oswa pi piti eleman yo pral trete premye soti nan etap 1 a 3, ak Lè sa a, nan lòt bò a.

Understand PCB board assembly process and feel the green charm of PCBD

Etap 4: enspeksyon kalite ak enspeksyon

Apre soude reflow, li posib ke eleman yo aliyen akòz kèk mouvman kòrèk nan plato PCB la, ki ka lakòz koneksyon sikwi kout oswa ouvè. These defects need to be identified, and this identification process is called inspection. Enspeksyon yo ka manyèl ak otomatik.

A. Manual check:

Because the PCB has small SMT components, visual inspection of the board for any misalignment or malfunction can cause technician fatigue and eye strain. Se poutèt sa, metòd sa a se pa posib pou davans tablo SMT akòz rezilta kòrèk. Sepandan, metòd sa a posib pou plak ki gen konpozan THT ak pi ba dansite eleman yo.

B. Deteksyon optik:

Metòd sa a posib pou gwo kantite PCBS. Metòd la itilize machin otomatik ki gen gwo pouvwa ak kamera rezolisyon segondè monte nan ang divès yo wè jwenti yo soude soti nan tout direksyon. Tou depan de bon jan kalite a nan jwenti a soude, limyè a ap reflete sou jwenti a soude nan ang diferan. This automatic optical inspection (AOI) machine is very fast and can process large quantities of PCBS in a very short time.

CX – ray inspection:

The X-ray machine allows technicians to scan the PCB to see internal defects. This is not a common inspection method and is only used for complex and advanced PCBS. If not used properly, these inspection methods may result in rework or PCB obsoletion. Enspeksyon yo dwe fèt regilyèman pou evite reta, travay ak depans materyèl.

Etap 5: THT fixation eleman ak soude

Konpozan nan twou yo komen sou anpil tablo PCB. These components are also called plated through holes (PTH). Kondwi eleman sa yo ap pase nan twou nan PCB la. Twou sa yo konekte ak lòt twou ak nan twou pa tras kwiv. Lè eleman THT sa yo mete ak soude nan twou sa yo, yo konekte elektrik ak lòt twou sou menm PCB la tankou sikwi ki fèt la. These PCBS may contain some THT components and many SMD components, so the welding method described above is not suitable for THT components in the case of SMT components such as reflow welding. Se konsa, de kalite prensipal yo nan THT eleman ki soude oswa reyini yo

A. Manyèl soude:

Manual welding methods are common and often require more time than an automated setup for SMT. Yon teknisyen tipikman asiyen nan insert yon eleman nan yon moman epi pase tablo a bay lòt teknisyen mete yon lòt eleman sou tablo a menm. Se poutèt sa, yo pral tablo sikwi a dwe deplase alantou liy lan asanble yo ka resevwa eleman nan PTH ranpli sou li. Sa fè pwosesis la long, ak anpil konsepsyon PCB ak konpayi fabrikasyon evite itilize eleman PTH nan desen sikwi yo. Men, eleman PTH la rete eleman pi renmen ak pi souvan itilize pa pifò konsèpteur sikwi.

B. Vag soude:

Vèsyon otomatik ki fonksyone nan soude manyèl se vag soude. Nan metòd sa a, yon fwa yo mete eleman PTH a sou PCB la, PCB la mete sou yon senti CONVEYOR epi li demenaje ale rete nan yon fou dedye. Isit la, vag soude fonn Splash nan substra a nan PCB la kote eleman yo mennen yo prezan. Sa a pral soude tout broch imedyatman. However, this method only works with single-sided PCBS and not double-sided PCBS, as melted solder on one side of the PCB can damage components on the other. Apre sa, deplase PCB la pou enspeksyon final la.

Etap 6: Enspeksyon final ak tès fonksyonèl

PCB se kounye a pare pou fè tès ak enspeksyon. This is a functional test in which electrical signals and power are given to the PCB at the specified pins and the output is checked at the specified test point or output connector. This test requires common laboratory instruments such as oscilloscopes, digital multimeters, and function generators

Tès sa a itilize pou tcheke karakteristik fonksyonèl ak elektrik PCB a epi valide aktyèl, vòltaj, analòg ak dijital siyal ak sikwi desen ki dekri nan kondisyon PCB yo.

Si nenpòt nan paramèt PCB la montre rezilta inakseptab, yo pral jete PCB la oswa trete dapre pwosedi estanda konpayi an. Faz tès la enpòtan paske li detèmine siksè oswa echèk nan tout pwosesis PCBA a.

Etap 7: Netwayaj final, fini ak anbake:

Now that the PCB has been tested in all aspects and declared normal, it is time to clean up unwanted residual flux, finger grime and oil. Nerjaveèi ki baze sou zouti netwayaj presyon ki wo lè l sèvi avèk dlo deyonize yo ase pou netwaye tout kalite pousyè tè. Dlo deyonize pa domaje sikwi PCB la. Apre lave, sèk PCB la ak lè konprese. PCB final la se kounye a pare yo dwe chaje ak anbake.