Tsananguro yeMaitiro Ekugadzira SMT PCB

SMT (tekinoroji yekugadzika pamusoro pechinhu) ndiyo nzira huru yekuunganidza mabhodhi emazuva ano: zvikamu zvinoiswa zvakananga pamapedhi pamusoro pechinhu uye zvinosungirirwa zvese panguva imwe chete muovheni inodzokororwa. Ndiyo inoita kuti zvigadzirwa zvemagetsi zvidiki, zvakakora, uye zvine simba rakawanda zvikwanisike. Gwaro iri rinotsanangura kuti SMT PCB chii uye kuti mutsetse wekugadzika unoshanda sei nhanho nhanho, kuti kugadzika pamusoro pechinhu kunoenderana sei neburi rinopinda, mapakeji akajairika ezvikamu, maitiro ekugadzira bhodhi rinoungana rakachena, uye kuti mapuranga apera anoongororwa uye kuyedzwa sei.

Zvinorevei SMT uye Nei Ichitonga

Muhunyanzvi hwekuisa pamusoro pechinhu, zvikamu zvine materminal madiki kana ma lead anosvetedza zvakananga kuma pads ari pamusoro pebhodhi, pane makumbo anopfuura nemaburi akaboorwa. Bhodhi rinogona kutakura zvikamu kumativi ese, uye mubatanidzwa wese unosvetedza kamwe chete kuburikidza neovheni inodzokororwa.

SMT inonyanya kukosha nekuda kwezvikonzero chaizvo. Zvikamu zvekuisa pamusoro pechinhu zvidiki zvikuru pane zvakafanana neburi razvo, saka mabhodhi akaomarara uye madiki. Maitiro acho anongoerekana agadzirwa otomatiki, izvo zvinoita kuti akurumidze, adzokororwe, uye asadhure zvakanyanya. Uye inotsigira mapakeji ane pitch yakanaka, ane pin-count yakawanda anodiwa nemachipisi emazuva ano. Kune anenge ese ma electronics aripo, SMT ndiyo yakajairika, ndosaka kugona kwemuunganidzi ari SMT line yayo, moyo wePCB assembly.

Mutsetse weSMT Assembly, Danho nedanho

Mutsetse weSMT muchina wakatevedzana, mumwe nemumwe achiita basa rimwe chete uye achipa bhodhi kune rinotevera. Kunzwisisa mashandiro anoita zvinhu kunoita kuti mitemo yekugadzira ive nemusoro gare gare.

1. Solder-paste kudhinda

Chinyoreso chesimbi isina ngura chakaiswa pamusoro pebhodhi risina chinhu, uye chinyoreso chesimbi, musanganiswa wezvidimbu zvidiki zvesimbi uye flux, chinosvinwa nepakati pemaburi ari muchinyorwa ichi kuenda kumapedhi. Maburi echinyoreso anodzora kuti chinyoreso chakawanda sei papedhi rega rega, uye kuwana huwandu ihwohwo hwakakodzera ndiko hwaro hwemajoini akanaka.

2. Kuongorora nekuisa paste (SPI)

Sisitimu inoongorora otomatiki paste yakadhindwa, vhoriyamu, nzvimbo, uye chimiro papedhi rega rega, zvinhu zvisati zvadzikira. Kubata dambudziko repaste pano kwakachipa zvikuru pane kuona chikanganiso mushure mekudzokororwa, saka SPI inzira yakakosha pakushanda zvakanaka.

3. Sarudza-uye-uise

Michina inomhanya zvikuru inotora zvikamu kubva mumareels nematireyi yozviisa zvakananga pamapedhi akanamirwa, zviuru zvenzvimbo paawa. Kusimba kwepaste kunoita kuti chikamu chimwe nechimwe chigare panzvimbo yacho kusvika chasangana. Kurongeka kwenzvimbo ndiko kunoita kuti zvikamu zvidiki nemachipisi akapfava zviunganidzwe zvakavimbika.

4. Reflow soldering

Bhodhi rinogara vanhu rinopfuura nemuovheni inodzokororwa ine chimiro chekupisa chinodzorwa zvakanaka, rinopisa, rinonyorovesa, chikamu chinonyungudutsa chinonyungudutsa (chezvinhu zvisina mutobvu, chikamu chinosvika 245 °C), rozotonhorera. Chinonyunguduka chinonyunguduka uye chinoita majoini echinonyungudutsa, chobva chaoma sezvo bhodhi richitonhora. Chimiro chekupisa chinogadziriswa kubhodhi nezvikamu zvaro, uye zvinhu zvinoda kutarisirwa zvakanyanya, ndosaka mapuranga anorema zvakanyanya achishandiswa nemaprofiles akakodzera kubatanidzwa kwesimbi.

5. Otomatiki Optical uye X-ray Kuongorora

Mushure mekudzokororwazve, automated optical inspection (AOI) inotarisa majoini ari kuonekwa uye nzvimbo yezvikamu nemakamera. Pamapakeji ane maconnection ari pasi pemuviri, akadai seQFN neBGA, X-ray inspection inoshandiswa kuona majoini akavanzwa. Pamwe chete vanosimbisa kuti soldering yabuda zvakanaka.

6. Mabhodhi ane mativi maviri

Kana zvikamu zvikaenda kumativi ese, divi rakareruka rinowanzo unganidzwa kutanga, bhodhi rinopindurwa uye divi rechipiri rinofambiswa, zvikamu zvinorema zvakanyanya zvichiiswa kudivi rekupedzisira kuitira kuti zvisakanganiswa. Kutevedzana uku kunoita kuti zvese zvirambe zviri panzvimbo yazvo kuburikidza nekudzokororwa kwechipiri.

SMT vs Through-Hole

Kuisa pamusoro pevhu hakuna kutsiva zvachose gomba rinopinda nepakati; rimwe nerimwe rine nzvimbo yaro, uye mabhodhi mazhinji anoshandisa ese ari maviri.

Maburi anoburitswa kuburikidza neburi achiri kuwana nzvimbo yemaconnectors anotora mutoro wemakanika, zvikamu zvesimba guru, uye chero chinhu chinobatsirwa nemaleads akasungirirwa mubhodhi. Zvigadzirwa zvakawanda zvechokwadi ndezvemhando dzakasiyana : zvikamu zvinoiswa pamusoro peburi zvinotanga zvadzoserwa, uye zvikamu zvinoburitswa kuburikidza neburi zvinowedzerwa nekusarudza kana kuti wave soldering. Muunganidzi ane hunyanzvi anomhanya maitiro ese ari maviri pabhodhi rimwe, izvo zvinokosha sezvo magadzirirwo achienda kuPCB assembly ine simba guru.

Mhando dzeSMT Package Dzakajairika

Zvikamu zveSMT zvinouya muzvikamu zvakasiyana-siyana, uye kuti chimwe nechimwe chinoongororwa sei zvinoenderana nekuti majoini acho anoonekwa here.

Maitiro acho ari nyore: zvikamu zvine malead anooneka (SOIC, QFP) uye chip passives zvinoongororwa nemaziso, nepo mapakeji ebottom-terminated uye ball-grid (QFN, BGA) anovanza majoini azvo uye anoda X-ray. Kuziva izvi kumberi kunoita kuti hurongwa hwekuongorora nedhizaini, fine-pitch uye hidden-joint parts zvionekwe zvakanyanya.

Kugadzira Bhodhi Rinogadzirira SMT

Bhodhi rinoungana zvakanaka rakagadzirirwa kuungana, kwete kungoshanda chete. Zvinhu zvikuru zvekugadzira ndeizvi:

• Tsika dzakanyatsorongeka uye mapatani enzvimbo. Mapedhi anofanira kuenderana nepatani inokurudzirwa nechikamu; tsoka dzisina kunaka dzinokonzera kuiswa uye zvikanganiso pakunamira.
• Maburi ekunamira ane hungwaru uye dhizaini yestencil. Maburi estencil anofanira kuisa vhoriyamu yakakodzera yekunamira, kunyanya kune zvikamu zvinopenya zvishoma nezvishoma uye zvinopera pasi.
• Vanyori venhema. Zviratidzo zvinoita kuti michina ienderane nemazvo, pamwe chete nezvishandiso zvemuno zvekushandisa michina inopinza bhora zvakanaka.
• Nzvimbo yakakwana. Siya nzvimbo pakati pezvikamu kuti zviiswe, zvidzoke, uye zviongororwe.
• Kuisa mapaneru uye maturusi ekushandisa. Gadzira mapaneru zvine hungwaru uchishandisa marara kuitira kuti bhodhi rifambe zvakanaka mumutsetse.
• Laminate chaiyo. Shandisa chinhu chine tembiricha yekuchinja kwegirazi (Tg) yakakodzera tembiricha isina mutobvu.
• Kubata kwemvura inobatwa nehunyoro (MSL). Zvimwe zvikamu zvinofanirwa kubikwa uye kubatwa zvakanaka zvisati zvadzorerwa mvura kuti zvisakuvadzwe nehunyoro.

Kugadzirisa izvi usati wagadzira kunodzivirira matambudziko mazhinji ekugadzira. Ongororo yeDFM yemugadziri yemahara inoongorora tsoka dzako, nzvimbo, fiducials, uye panelization zvichienderana nemutsetse chaiwo weSMT uye inoratidza matambudziko achiri akachipa kugadzirisa. Hunhu hwebhodhi risina chinhu hunokoshawo, sezvo kubatanidzwa kwakanaka chete sekugadzirwa kwePCB pasi payo, uye magadzirirwo ekumhanya kwepamusoro kana RF anowedzera zvimwe zvinodiwa zvakabatana nekugadzirwa kwePCB nekukurumidza uye zvinhu zvisingarasikirwe zvakanyanya.

Mbiri Yekufefeterazve, Danho Nedanho

Ovheni inodzokororwazve ndipo panoumbwa majoini e solder, uye tembiricha yayo inogadziriswa kubhodhi nezvinhu zviri mairi. Profaili yakajairika inofamba nematanho mana.

Kugadzirisa danho rega rega nemazvo kunokosha: kumhanya kwakanyanya kunogona kukuvadza zvikamu kana kukonzera zvikanganiso, kunyorova kushoma kunosiya kupisa kusina kuenzana, uye kukwirira kusiri iko kunoita kuti majoini asashande zvakanaka kana kuti atonhore. Hunhu hwebhodhi hunoenderana nehuremu hwezvinhu, ndosaka ma substrates anorema zvakanyanya anoda ma profiles akagadzirwa anoshandiswa mukubatanidza simbi nepakati.

Ma alloys e solder: asina mutobvu uye ane mutobvu

Zvizhinji zvezvigadzirwa zviripo zvino zvinoshandisa solder isina lead, inowanzova tin-silver-copper (SAC) alloy, iyo inonyungudutsa kupisa saka inoda reflow peak yakakwira uye laminate yakayerwa. Leaded (tin-lead) solder inonyunguduka patembiricha yakaderera uye ichiri kushandiswa mune mamwe maapplications chaiwo. Alloy iyi inoisa tembiricha yepamusoro uye inokanganisa sarudzo yezvinhu, saka inosarudzwa pamwe chete ne laminate yebhodhi panguva yekugadzira PCB.

Kuongorora, Kuedza, uye Hunhu

Hunhu hweSMT hunovakwa kuburikidza nekuongorora pamatanho akasiyana-siyana uye hunosimbiswa nekuyedzwa pakupera.

Kuongorora panguva yekuita izvi

• SPI inoongorora paste inosungirirwa isati yaiswa.
• AOIs inotarisa nzvimbo uye majoini anoonekwa mushure mekubudazve kwemvura.
• X-ray inoongorora nzvimbo dzakavanzwa dzemapakeji eQFN neBGA.

Kuedza bhodhi rakapedzwa

• Inoshanda bvunzo inopa simba bhodhi uye inosimbisa kuti rinoita sezvakarongwa.
• Bvunzo yemudunhu (ICT) or bvunzo yekubhururuka-yekuongorora inoongorora mambure ega ega nezvimwe zvikamu zvemagetsi.

Kuongorora nekuyedza ma layering nenzira iyi kunobata zvikanganiso nekukurumidza uye kunosimbisa kuti bhodhi rinoshanda risati ratumirwa. Sezvo huwandu huchikura, kutonga kwemaitiro ehuwandu kunoita kuti mutsetse urambe wakafanana kuitira kuti bhodhi rega rega riite serekutanga, musiyano uripo pakati pekuvaka kamwe chete nekugadzirwa kwakavimbika.

Kuungana kweSMT inzira chaiyo, inotevedzana otomatiki, inonamira, inoongorora, inoisa, inofambisazve, inoongorora, iyo inoshandura bhodhi risina chinhu nereel yezvikamu kuita chigadzirwa chapera. Dhizaini yemaitiro iwayo kubva pakutanga, uye mhedzisiro yacho inoungana zvakanaka uye inoyedzwa zvakanaka. Unogona kuverenga zvakawanda nezveHighleap Electronics uye kugona kwedu kweSMT nehybrid assembly.

Mibvunzo Inonyanya Kubvunzwa

Chii chinonzi SMT?

Tekinoroji yekuisa pamusoro. Zvikamu zvinoiswa pamapedhi ari pamusoro pebhodhi uye zvinosungirirwa muovheni inodzokororwa, pane kuva netambo dzinopfuura nemaburi akaboorwa. Inogonesa kuungana kudiki, kwakakora, uye kunoshanda nemagetsi emazuva ano.

Matanho ekubatanidza SMT ndeapi?

Kudhinda nekuisa solder-namate kuburikidza nestencil, kuongorora nekuisa solder-namate (SPI), kusarudza-nekuisa zvikamu, kudzoreredza simbi kuburikidza neovheni inodzorwa nekupisa, uye kuongorora otomatiki kwe optical ne X-ray. Mabhodhi ane mativi maviri anotanga nerutivi rwakareruka, wobva wadzvanya womhanyisa divi rechipiri.

Sei zvikamu zveBGA neQFN zvichida kuongororwa neX-ray?

Makontena avo ekubatanidza anoiswa pasi pepakeji, maBGA ari pagridi yemabhora, maQFN ari pamagumo epasi, saka makamera haakwanise kuona majoini. Kuongorora kweX-ray kunoongorora kuburikidza nepakeji kuti vaone kuti majoini akavanzwa akagadzirwa nemazvo.

Zvikamu zveSMT nezviri mukati megomba zvinogona kuva pabhodhi rimwe chete here?

Ehe, uye zvigadzirwa zvakawanda zvakagadzirwa nemahybrid. Zvikamu zvinosungirirwa pamusoro pechinhu zvinotanga zvadzoserwa mvura, uye zvikamu zvinopinda nepakati zvinowedzerwa nekusarudza kana kuti wave soldering. Maburi anochengeterwa maconnectors, zvikamu zvine simba guru, uye zvikamu zvinotora simba remakanika.

Chii chinoita kuti bhodhi rive nyore kubatanidza neSMT?

Makwara akakodzera, maburi akagadzirwa zvakanaka, zvinhu zvinokwanisa kurongeka, nzvimbo yakakwana pakati pezvikamu, mapaneru ane mwero, laminate yakatarwa kuti idzoke patembiricha, uye kubata kwakakodzera kunodzivirira hunyoro. Ongororo yeDFM isati yagadzirwa inoratidza kuti izvi zvakarurama.

Bhodhi reSMT rakaungana rinoedzwa sei?

Kuongorora panguva yekushanda (SPI, AOI, uye X-ray yemajoini akavanda) kunobata zvikanganiso zvekusungirirwa, uye bhodhi rakapedzwa rinosimbiswa nekuyedzwa kunoshanda uye, kana richishandiswa, kuyedzwa kwemu-circuit kana flying-probe. Kudzora maitiro ehuwandu hwezvinhu kunoita kuti mhedzisiro ienderane nehukuru.