E le karolo ea bohlokoa ea lihlahisoa tsa elektroniki, boto ea potoloho e hatisitsoeng (PCB) e bapala karolo ea bohlokoa ho elellleng tšebetso ea lihlahisoa tsa elektroniki, e lebisang ho bohlokoa bo ntseng bo eketseha ba moralo oa PCB, hobane ts’ebetso ea moralo oa PCB e supa ts’ebetso le litšenyehelo tsa lihlahisoa tsa elektroniki. Moralo o motle oa PCB o ka boloka lihlahisoa tsa elektroniki ho tsoa mathateng a mangata, ka hona ea netefatsa hore lihlahisoa li ka etsoa hantle le ho fihlela litlhoko tsohle tsa lits’ebetso tse sebetsang.

Har’a likarolo tsohle tse tlatsetsang ho moralo oa PCB, Design Design (DFM) e bohlokoa haholo hobane e hokahanya moralo oa PCB le tlhahiso ea PCB molemong oa ho fumana mathata kapele le ho a rarolla ka nako nakong eohle ea bophelo ba lihlahisoa tsa elektroniki. One myth is that the complexity of PCB design will increase as manufacturability of electronics is considered at the PCB design stage. In the design life cycle of electronic products, DFM can not only make electronic products participate in automatic production smoothly, and save labor costs in the manufacturing process, but also effectively shorten the manufacturing time to ensure the timely completion of the final electronic products.

Thibelo ea PCB

Ka ho kopanya tlhahiso le moralo oa PCB, moralo oa tlhahiso ke ntlha ea bohlokoa e lebisang ho tlhahiso e sebetsang, boleng bo holimo le theko e tlase. The research of PCB manufacturability covers a wide range, usually divided into PCB manufacturing and PCB assembly.

LPCB production

For PCB manufacturing, the following aspects should be considered: PCB size, PCB shape, process edge and Mark point. Haeba likarolo tsena li sa tsotelloe ka botlalo mohatong oa moralo oa PCB, mechini e itšebetsang ea chip laminating e kanna ea se khone ho amohela liboto tsa PCB tse kgethiloeng ntle le haeba ho nkuoa mehato e meng ea ts’ebetso. Ho mpefatsa boemo le ho feta, lipoleiti tse ling li ke ke tsa iketsa ka botsona li sebelisa ho tjheseletsa ka letsoho. As a result, the manufacturing cycle will be longer and labor costs will increase.

1. PCB size

Setsi se seng le se seng sa chip se na le boholo ba sona ba PCB, bo fapaneng ho latela maemo a sehokelo se seng le se seng. Mohlala, chip installer e amohela boholo ba PCB bo boholo ba 500mm * 450mm le bonyane ba PCB boholo ba 30mm * 30mm. Sena ha se bolele hore re ke ke ra sebetsana le likarolo tsa boto ea PCB tse nyane ho feta 30mm ka 30mm, mme re ka ts’epa liboto tsa jigsaw ha ho hlokahala boholo bo bonyenyane. Ha o ka itšetleha feela ka ho kenya letsoho le litjeo tsa basebetsi li ntse li phahama ‘me methati ea tlhahiso e tsoile taolong, mechini ea chip SMT e ke ke ea amohela liboto tsa PCB tse kholo haholo kapa tse nyane haholo. Therefore, in the PCB design stage, the PCB size requirements set by automatic installation and manufacturing must be fully considered, and it must be controlled within the effective range.

Palo e latelang e bonts’a tokomane ea moralo oa boto ea PCB e phethetsoeng ke software ea Huaqiu DFM. Joaloka boto ea 5 × 2, yuniti ka ‘ngoe ea sekwere ke sekhechana se le seng, se lekanyang 50mm ka 20mm. The connection between each unit is achieved by V-cut/V-scoring technology. In this image, the entire square is shown with a final size of 100mm by 100mm. Ho latela litlhoko tse kaholimo, ho ka phetheloa hore boholo ba boto bo kahara mohala o amohelehang.

2. PCB shape

In addition to PCB size, all chip SMT machines have requirements for PCB shape. PCB e tloaelehileng e lokela ho ba sebopeho se likhutlo li ‘ne le bolelele ho isa bophara ba 4: 3 kapa 5: 4 (e molemohali). If the PCB is irregularly shaped, additional measures must be taken prior to SMT assembly, resulting in increased costs. Ho thibela sena hore se se ke sa etsahala, PCB e tlameha ho etsoa ka sebopeho se tšoanang nakong ea karolo ea moralo oa PCB ho fihlela litlhoko tsa SMT. Leha ho le joalo, ho thata ho e etsa ka mokhoa ona. Ha sebopeho sa lihlahisoa tse ling tsa elektroniki se tlameha ho ba se sa tloaelehang, mekoti ea setempe e tlameha ho sebelisoa ho fa PCB ea ho qetela sebopeho se tloaelehileng. Ha li bokelletsoe, li-baffles tse thusang tse sa hlokahaleng li ka tlosoa ho PCB ho fihlela litlhoko tsa ho kenya le tsa sebaka ka bo eona.

Setšoantšo se ka tlase se bontša PCB ka sebopeho se sa tloaelehang, ‘me bohale ba ho e lokisa bo eketsoa ke software ea Huaqiu DFM. The whole circuit board size is 80mm * 52mm, and the square area is the size of the actual PCB. The size of the upper right corner area is 40mm by 20mm, which is the auxiliary craft edge produced by the bridge of the stamp hole.

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3. Lehlakore la tšebetso

To meet the requirements of automatic manufacturing, process edges must be placed on the PCB to secure the PCB.

Ka PCB sethaleng moralo, 5mm lohle thulaganyou e bohale lokela ho behella ka thōko esale pele, ntle le siea dikarolo efe kapa efe le wiring. Tataiso ea tekheniki hangata e beoa ka lehlakoreng le lekhutšoane la PCB, empa lehlakore le lekhutšoane le ka khethoa ha karolo e fapaneng e feta 80%. Kamora kopano, bohale ba ts’ebetso bo ka tlosoa e le karolo ea tlhahiso e thusang.

4. Mark point

For PCBS with components installed, Mark points should be added as a common reference point to ensure that component locations are accurately determined for each assembly device. Ka hona, lintlha tsa Mark ke li-benchmark tsa tlhahiso ea SMT tse hlokahalang bakeng sa tlhahiso e ikemetseng.

Components require 2 Mark points and PCBS require 3 Mark points. These marks should be placed on the edges of the PCB board and cover all SMT components. Bohareng ba sebaka lipakeng tsa Mark point le bohale ba poleiti e lokela ho ba bonyane 5mm. Bakeng sa li-PCBS tse nang le mahlakore a mabeli a SMT, lintlha tsa Mark li lokela ho beoa ka mahlakore ka bobeli. If the components are too close together to place Mark points on the board, they can be placed on the edge of the process.

LPCB assembly

Kopano ea PCB, kapa PCBA ka bokhutšoanyane, ha e le hantle ke ts’ebetso ea likarolo tsa ho tjheseletsa mapolanka a se nang letho. E le hore ho kopana le ditlhoko tsa ho etsa thepa jarolla ka ho iketsa, PCB kopano na le tse ling tse ditlhoko tsa sephutheloana kopano le moralo kopano.

1. Ho paka likarolo

Nakong ea moralo oa PCBA, haeba liphutheloana tsa likarolo li sa fihlelle maemo a nepahetseng ‘me likarolo li le haufi haholo, ho kenya ka boiketsetso ho ke ke ha etsahala.

Bakeng sa ho fumana sephutheloana se setle ka ho fetesisa, software ea moralo oa litsebi ea EDA e lokela ho sebelisoa ho latela litekanyetso tsa machabeng tsa ho paka likarolo. During PCB design, the aerial view area must not overlap with other areas, and the automatic IC SMT machine will be able to accurately identify and mount the surface.

2. Component layout

Karolo ea likarolo ke mosebetsi oa bohlokoa ho moralo oa PCB hobane ts’ebetso ea eona e amana ka kotloloho le ho rarahana ha ponahalo ea PCB le ts’ebetso ea tlhahiso.

Nakong ea moralo oa likarolo, bokaholimo ba kopano ea likarolo tsa SMD le THD bo lokela ho etsoa qeto. Mona, re beha bokapele ba PCB joalo ka karolo ea A lehlakoreng le ka morao e le karolo ea karolo ea B. The assembly layout should consider the assembly form, including single layer single package assembly, double layer single package assembly, single layer mixed package assembly, Side A mixed package and side B single package assembly and side A THD and side B SMD assembly. Kopano e fapaneng e hloka lits’ebetso le mekhoa e fapaneng ea ho etsa. Therefore, in terms of component layout, the best component layout should be selected to make manufacturing simple and easy, so as to improve the manufacturing efficiency of the whole process.

In addition, consideration must be given to the orientation of component layout, spacing between components, heat dissipation, and component height.

Ka kakaretso, sebopeho sa motsoako se lokela ho ts’oana. Components are laid out in accordance with the principle of minimum tracking distance, based on which components with polarity markers should have uniform polarity directions, and components without polarity markers should be neatly aligned along the X or Y axis. Bophahamo ba karolo e lokela ho ba ho fihlela ho 4mm, ‘me tsela ea phetiso pakeng tsa karolo le PCB e lokela ho ba 90 °.

Ho ntlafatsa lebelo la ho tjheseletsa likarolo le ho tsamaisa tlhahlobo e latelang, sebaka se pakeng tsa likarolo se lokela ho ts’oana. Components in the same network should be close to each other and a safe distance should be left between different networks according to the voltage drop. Silkscreen and pad must not overlap, otherwise components will not be installed.

Due to the actual operating temperature of the PCB and the thermal characteristics of the electrical components, heat dissipation should be considered. Sebopeho sa likaroloana se lokela ho shebana le mocheso oa mocheso. Haeba ho hlokahala, sebelisa fan kapa sinking ea mocheso. Ho lokela ho khethoa li-radiator tse loketseng lisebelisoa tsa motlakase ‘me likarolo tse hlokolosi tsa mocheso li lokela ho beoa hole le mocheso. Karolo e phahameng e lokela ho beoa kamora karolo e tlase.

Lintlha tse ling li lokela ho tsepamisoa ho PCB DFM, ‘me boiphihlelo bo lokela ho bokelloa ts’ebetsong. Mohlala, litlhoko tsa moralo oa li-PCB tse nang le lebelo le phahameng li na le litlhokahalo tse khethehileng tsa impedance mme li lokela ho buisanoa le moetsi oa boto pele ho tlhahiso ea ‘nete ho tseba impedance le tlhaiso-leseling. Bakeng sa ho itokisetsa tlhahiso bakeng sa liboto tse nyane tsa PCB tse nang le likhoele tse teteaneng, bophara ba wiring bo boholo le bophara ba tlhahiso ea bophara ba lesoba bo lokela ho tšohloa le moetsi oa PCB ho netefatsa tlhahiso e boreleli ea li-PCBS tsena.