N’ihe banyere teknụzụ ọgbara ọhụrụ, ụwa na -eto n’ike n’ike, na mmetụta ya nwere ike ịbata ngwa ngwa na ndụ anyị kwa ụbọchị. 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. Isi nke ngwaọrụ ndị a bụ injinịa eletriki, isi ya bụkwa bọọdụ sekit biri ebi (PCB).

PCB na -abụkarị akwụkwọ ndụ akwụkwọ ndụ ma bụrụ ahụ siri ike nwere ihe eletrọnịkị dị iche iche dị na ya. These components are welded to the PCB in a process called “PCB assembly” or PCBA. PCB nwere mkpụrụ osisi nke ejiri fiberglass mee, akwa ọla kọpa nke na -eme nchọta, oghere mebere ihe mejupụtara ya, na akwa nwere ike ime n’ime na mpụga. Na RayPCB, anyị nwere ike nye ihe ruru 1-36 maka PROTOTYPES nke nwere ọtụtụ akwa na akwa 1-10 maka ọtụtụ PCB maka mmepụta olu. For single-sided and double-sided PCBS, an outer layer exists but no inner layer.

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. Ihe mkpuchi ịgbado ọkụ ga-enye ohere ka akụrụngwa ahụ zere ịbịaru nso na egwu ma ọ bụ ihe ndị ọzọ.

A na -eji akara ọla kọpa ebufe akara elektrọnik site n’otu isi gaa na nke ọzọ na PCB. These signals can be high-speed digital signals or discrete analog signals. Enwere ike ime wires ndị a oke iji nye ike/ike maka inye ọkụ ọkụ.

In most PCBS that provide high voltage or current, there is a separate grounding plane. Components on the top layer are connected to the internal GND plane or internal signal layer via “Vias”.

A na -achịkọta ihe na PCB iji mee ka PCB rụọ ọrụ dịka emebere ya. The most important thing is PCB function. Ọ bụrụgodi na etinyeghị obere ihe mgbochi SMT n’ụzọ ziri ezi, ma ọ bụ ọbụlagodi na ebipụrụ obere egwu na PCB, PCB nwere ike ọ gaghị arụ ọrụ. Ya mere, ọ dị mkpa ka akpọkọta ngwakọ n’ụzọ dabara adaba. A na -akpọ PCB mgbe a na -akpọkọta ihe PCBA ma ọ bụ PCB mgbakọ.

Dabere na nkọwapụta nke onye ahịa ma ọ bụ onye ọrụ kọwara, ọrụ nke PCB nwere ike ịdị mgbagwoju anya ma ọ bụ dị mfe. PCB size also varies according to requirements.

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

PCB oyi akwa na imewe

Dịka e kwuru n’elu, enwere ọtụtụ akara mgbaama n’etiti akwa mpụta. Now we will discuss the types of outer layers and functions.

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

1-Ntughari: Nke a bụ efere siri ike nke ihe FR-4 nke ihe mejupụtara ya “jupụtara” ma ọ bụ welded. This provides rigidity for the PCB.

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- nkpuchi mkpuchi: A na-etinye ya na elu na ala nke PCB. This is used to create non-conducting areas of the PCB and insulate the copper traces from each other to protect against short circuits. Ihe mkpuchi ịgbado ọkụ na -ezerekwa ịgbado akụkụ ndị achọghị ma hụ na solder na -abanye na mpaghara maka ịgbado ọkụ, dị ka oghere na mpe mpe akwa. 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. Ihuenyo ihuenyo na -enye ozi dị mkpa gbasara PCB.

There are 3 types of PCBS according to the substrate classification

1- Rigid PCB:

PCB bụ ọtụtụ ngwaọrụ PCB anyị na -ahụ n’ụdị PCB dị iche iche. Ndị a siri ike, siri ike ma sie ike PCBS, nwere ọkpụrụkpụ dị iche iche. The main material is fiberglass or simple “FR4”. FR4 na-anọchi anya “ire ọkụ retarder-4”. Njirimara na-emenyụ onwe ya nke FR-4 na-eme ka ọ baa uru maka iji ọtụtụ ngwaọrụ elektrọnik ụlọ ọrụ siri ike. The FR-4 has thin layers of copper foil on both sides, also known as copper-clad laminates. A na-ejikarị ihe mkpuchi mkpuchi ọla kọpa Fr-4 na amplifiers ike, ịgbanye ọnọdụ ike, ndị ọkwọ ụgbọ ala servo, wdg. N’aka nke ọzọ, mkpụrụ osisi PCB ọzọ siri ike nke a na -ejikarị na ngwa ụlọ yana ngwaahịa IT a na -akpọ PCB phenolic akwụkwọ. Ha dị nfe, njupụta dị ala, dị ọnụ ala ma dịkwa mfe ịkụ. Ihe mgbako, igodo na ụmụ oke bụ ụfọdụ ngwa ya.

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.Enwere ike iji ụdị PCBS ndị a maka ngwa chọrọ akụrụngwa ọkụ dị ka ọkụ ọkụ dị elu, diodes laser, wdg.

Installation technology type:

SMT: SMT na -anọchite anya “teknụzụ elu ugwu”. Akụkụ SMT pere mpe ma bịa na ngwugwu dị iche iche dị ka 0402,0603 1608 maka ndị na -eguzogide ma ọ bụ capacitors. N’otu aka ahụ, maka eserese eserese agbakwunyere, anyị nwere SOIC, TSSOP, QFP na BGA.

Mgbakọ SMT siri ezigbo ike maka aka mmadụ yana ọ nwere ike bụrụ usoro nhazi oge, yabụ na -eme ya n’ụzọ bụ isi na akpaaka akpaaka na robots.

THT: THT na-anọchite anya teknụzụ oghere. 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.

Mgbakọ usoro mkpa:

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. Ndị nrụpụta ga -emerịrị usoro DFM ndị a iji hụ na PCB enweghị ntụpọ.

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 notch/isi isi ga -enyocharịrị.

Mmewere chọrọ ebe mgbaba ọkụ kwesịrị inwe oghere zuru oke iji nabata ihe ndị ọzọ ka ọkụ ọkụ anaghị emetụ aka.

2-Hole and through-hole spacing:

The spacing between holes and between holes and traces should be checked. Mpekere na oghere agaghị agabiga.

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. Na RayPCB, anyị na-eji akụrụngwa OEM nke ọgbara ọhụrụ iji nye ọrụ PCB OEM, ịgbanye ọkụ, nnwale kaadị PCB na mgbakọ SMT.

Mgbakọ PCB (PCBA) usoro nzọụkwụ:

Kwụpụ 1: Tinye akwụkwọ mmado site na iji template

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. Igwe eji arụ ọrụ na -ejikọ ndebiri na PCB, a na -etinyekwa mpekere solder ahụ na oghere niile dị na bọọdụ site na ngwa. Apply solder paste evenly with applicator. Ya mere, ekwesịrị iji pasta solder kwesịrị ekwesị na ngwa. Mgbe ewepụrụ onye na -achọ ya, mado ahụ ga -adịgide na mpaghara PCB chọrọ. Gray solder paste 96.5% nke tin, nwere 3% ọlaọcha na 0.5% ọla kọpa, enweghị isi. After heating in Step 3, the solder paste will melt and form a strong bond.

Step 2: Automatic placement of components:

Nzọụkwụ nke abụọ nke PCBA bụ idobe ihe SMT na PCB. A na -eme nke a site na iji robot ahọpụtara na ebe. Na ọkwa imewe, onye nrụpụta mepụtara faịlụ wee nye ya robot na -akpaghị aka. Faịlụ a nwere nhazi X, Y nke ahaziri nke ngwa ọ bụla ejiri na PCB wee chọpụta ọnọdụ nke ihe niile mejupụtara. 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.

Tupu ọbịbịa nke igwe robọtụ na igwe idobe ihe, ndị na -ahụ maka nka ga -eji tweezers na -eburu akụrụngwa wee debe ya na PCB site n’iji nlezianya na -ele ebe ahụ ma zere aka ọ bụla. This results in high levels of fatigue and poor vision for technicians, and leads to a slow PCB assembly process for SMT parts. Ya mere, enwere ike imehie ihe dị elu.

Ka teknụzụ na -eto, robots na -akpaghị aka na -eburu ma debe ihe na -ebelata ọrụ ndị ọrụ aka, na -eme ka itinye ngwa ngwa na nke ziri ezi. Ndị robots ndị a nwere ike ịrụ ọrụ 24/7 na -enweghị ike ọgwụgwụ.

Nzọụkwụ 3: Reflow ịgbado ọkụ

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. Ọnọdụ okpomọkụ zuru ezu iji gbazee solder. Onye na -ere ahịa agbazere na -ejigide akụrụngwa ya na PCB wee mepụta nkwonkwo. After high temperature treatment, the PCB enters the cooler. These coolers then solidify the solder joints in a controlled manner. Nke a ga -ewepụta njikọ na -adịgide adịgide n’etiti akụkụ SMT na PCB. N’ihe banyere PCB nwere ihu abụọ, dị ka akọwara n’elu, a ga-ebu ụzọ lebara akụkụ PCB nwere obere ihe ma ọ bụ obere ihe site na nzọụkwụ 1 ruo 3, wee gafee n’akụkụ nke ọzọ.

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

Step 4: Quality inspection and inspection

Mgbe ịgbanyechara mgbagharị, ọ ga -ekwe omume na -ahazighị akụrụngwa n’ihi ụfọdụ mmegharị adịghị mma na tray PCB, nke nwere ike ibute njikọ sekit dị mkpirikpi ma ọ bụ mepere emepe. These defects need to be identified, and this identification process is called inspection. Nnyocha nwere ike ịbụ akwụkwọ ntuziaka na akpaghị aka.

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. Yabụ, usoro a agaghị ekwe omume maka mbadamba SMT n’ihu n’ihi nsonaazụ ezighi ezi. Agbanyeghị, usoro a ga -ekwe omume maka efere nwere akụkụ THT na njupụta nke akụkụ dị ala.

B. Nchọpụta anya:

Usoro a ga -ekwe omume maka nnukwu PCBS. Usoro a na -eji igwe na -akpaghị aka nwere ike dị elu na igwefoto mkpebi dị elu etinyere n’akụkụ dị iche iche iji lelee nkwonkwo solder site n’akụkụ niile. Dabere na mma nke nkwonkwo solder, ọkụ ahụ ga -egosipụta na -erepụ ya na akụkụ dị iche iche. 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. Ọ dị mkpa ka a na -eme nyocha mgbe niile iji zere igbu oge, ọrụ na ụgwọ ihe.

Kwụpụ 5: idozi akụkụ THT na ịgbado ọkụ

Akụkụ oghere nwere oghere na ọtụtụ bọọdụ PCB. These components are also called plated through holes (PTH). Ndị na -eduzi ihe ndị a ga -agafe oghere dị na PCB. A na -ejikọ oghere ndị a na oghere ndị ọzọ yana site na oghere site na akara ọla kọpa. Mgbe etinyere ma tinye ihe THT n’ime oghere ndị a, a na -ejikọ eletrik na oghere ndị ọzọ n’otu PCB dị ka sekit a haziri. 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. So the two main types of THT components that are welded or assembled are

A. Manual welding:

Manual welding methods are common and often require more time than an automated setup for SMT. A na -ekenyekarị onye na -ahụ maka teknụzụ ka ọ tinye otu akụrụngwa n’otu oge wee nyefee ndị na -ahụ maka teknụzụ ndị ọzọ itinye osisi ọzọ n’otu bọọdụ ahụ. Therefore, the circuit board will be moved around the assembly line to get the PTH component to fill on it. This makes the process lengthy, and many PCB design and manufacturing companies avoid using PTH components in their circuit designs. Mana akụrụngwa PTH ka bụ ihe kacha amasị na nke ọtụtụ ndị na -emepụta sekit na -eji.

B. Ịkwa akwa:

Ụdị akpaaka nke ịgbado ọkụ ntuziaka bụ ịgbado ọkụ. N’ime usoro a, ozugbo etinye ihe PTH na PCB, a na -etinye PCB na eriri ebu ma kwaga ya na oven a raara nye. N’ebe a, ebili mmiri nke solder wụrụ awụ na -abanye n’ime mkpụrụ PCB ebe akụrụngwa na -eduga dị. Nke a ga -agbado atụdo niile ozugbo. 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. Mgbe nke a gasị, bughaa PCB maka nyocha ikpeazụ.

Nzọụkwụ 6: Nnyocha ikpeazụ na nnwale arụmọrụ

PCB dị njikere ugbu a maka nnwale na nyocha. 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

A na -eji nnwale a lelee njirimara arụmọrụ na ọkụ eletrik nke PCB ma gosipụta nke ugbu a, voltaji, akara analog na akara dijitalụ na atụmatụ sekit akọwapụtara na ihe PCB chọrọ.

Ọ bụrụ na ihe ọ bụla nke PCB gosipụtara nsonaazụ na -adịghị anakwere, PCB ga -atụfu ma ọ bụ kpochapụ dị ka usoro ụlọ ọrụ ọkọlọtọ si dị. Oge nnwale dị mkpa n’ihi na ọ na -ekpebi ihe ịga nke ọma ma ọ bụ ọdịda nke usoro PCBA niile.

Nzọụkwụ 7: Nhicha ikpeazụ, imecha na mbufe:

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. Ngwongwo nhicha dị elu nke igwe anaghị agba nchara na -eji mmiri deionized zuru ezu iji hichaa unyi niile. Mmiri deionized anaghị emebi okirikiri PCB. Mgbe ịsachara, were ikuku ikuku kpoo PCB. PCB ikpeazụ dị njikere ugbu a ịkwakọba na ibufe ya.