Kev tsim ntawm multilayer PCB (luam tawm Circuit Board) tuaj yeem nyuaj heev. Qhov tseeb tias tus qauv tsim txawm tias yuav tsum tau siv ntau tshaj ob txheej txheej txhais tau hais tias yuav tsum muaj cov xov tooj ntawm cov khoom siv hluav taws xob yuav tsis tuaj yeem ntsia tau rau saum toj thiab hauv qab. Txawm tias thaum lub voj voog ua haujlwm zoo nyob rau hauv ob txheej txheej txheej, tus tsim PCB tuaj yeem txiav txim siab ntxiv lub hwj chim thiab cov txheej hauv av sab hauv los kho qhov kev ua haujlwm tsis zoo.

Los ntawm cov teeb meem thermal mus rau EMI (Electromagnetic Interference) lossis ESD (Electrostatic Discharge) teeb meem, muaj ntau yam sib txawv uas tuaj yeem ua rau kev ua haujlwm zoo tshaj plaws thiab yuav tsum tau daws thiab tshem tawm. Txawm li cas los xij, txawm hais tias koj thawj txoj haujlwm ua tus tsim qauv yog los kho cov teeb meem hluav taws xob, nws tseem ceeb sib npaug tsis txhob tsis quav ntsej txog kev teeb tsa lub cev ntawm lub rooj tsav xwm hluav taws xob. Hluav taws xob cov boards tseem tuaj yeem khoov lossis twist, ua rau kev sib dhos nyuaj lossis txawm tias ua tsis tau. Hmoov zoo, kev saib xyuas rau PCB lub cev kev teeb tsa thaum lub sij hawm tsim qauv yuav txo cov teeb meem kev sib dhos yav tom ntej. Qhov sib npaug-rau-txheej txheej yog ib qho tseem ceeb ntawm cov khoom siv hluav taws xob ruaj khov.

01
Sib npaug PCB stacking

Balanced stacking yog ib pawg nyob rau hauv uas txheej txheej saum npoo thiab ntoo khaub lig-sectional qauv ntawm cov ntawv luam tawm Circuit Board yog ob qho tib si tsim nyog symmetrical. Lub hom phiaj yog tshem tawm cov cheeb tsam uas yuav deform thaum raug kev nyuaj siab thaum lub sij hawm tsim khoom, tshwj xeeb tshaj yog thaum lub sij hawm lamination. Thaum lub rooj tsav xwm Circuit Court deformed, nws yog ib qho nyuaj rau nteg nws tiaj tus rau kev sib dhos. Qhov no yog tshwj xeeb tshaj yog muaj tseeb rau Circuit Court boards uas yuav tsum tau sib sau ua ke ntawm automated nto mount thiab tso cov kab. Nyob rau hauv qhov xwm txheej hnyav, deformation tuaj yeem cuam tshuam kev sib dhos ntawm PCBA sib dhos (lub rooj sib tham sib dhos) rau hauv cov khoom kawg.

IPC cov qauv tshuaj ntsuam xyuas yuav tsum tiv thaiv kom tsis txhob muaj lub rooj tsav xwm khoov loj tshaj plaws kom ncav cuag koj cov cuab yeej. Txawm li cas los xij, yog tias cov txheej txheem ntawm PCB cov chaw tsim khoom tsis yog tag nrho ntawm kev tswj hwm, ces cov hauv paus ntsiab lus ntawm kev khoov feem ntau tseem cuam tshuam nrog kev tsim. Yog li ntawd, nws raug nquahu kom koj ua tib zoo xyuas cov txheej txheem PCB thiab ua qhov tsim nyog hloov kho ua ntej tso koj thawj daim ntawv xaj. Qhov no tuaj yeem tiv thaiv cov qoob loo tsis zoo.

02
Circuit Board ntu

Ib qho laj thawj uas cuam tshuam txog kev tsim qauv yog tias lub rooj tsav xwm luam tawm yuav tsis tuaj yeem ua tiav qhov kev ua tau zoo vim tias nws cov qauv ntoo khaub lig yog asymmetric txog nws qhov chaw. Piv txwv li, yog tias tus qauv 8-txheej txheej siv 4 lub teeb liab txheej los yog tooj liab tshaj qhov chaw npog cov dav hlau hauv zos thiab 4 lub dav hlau zoo hauv qab no, kev ntxhov siab ntawm ib sab ntawm pawg txheeb ze rau lwm qhov yuav ua rau tom qab etching, thaum cov khoom siv. yog laminated los ntawm cua sov thiab nias, tag nrho cov laminate yuav deformed.

Yog li ntawd, nws yog ib qho kev xyaum zoo los tsim cov pawg kom cov hom tooj liab txheej (dav hlau lossis teeb liab) yog mirrored nrog kev hwm rau qhov chaw. Hauv daim duab hauv qab no, hom sab saum toj thiab hauv qab sib phim, L2-L7, L3-L6 thiab L4-L5 phim. Tej zaum qhov kev pab cuam tooj liab ntawm tag nrho cov teeb liab txheej yog sib piv, thaum lub planar txheej yog tsim los ntawm cov khoom cam khwb cia tooj liab. Yog tias qhov no yog qhov teeb meem, ces lub rooj tsav xwm hauv Circuit Court muaj lub sijhawm zoo los ua kom tiav lub tiaj tiaj tiaj tiaj, uas yog qhov zoo tagnrho rau kev sib sau ua ke.

03
PCB dielectric txheej thickness

Nws kuj yog ib tug cwj pwm zoo kom sib npaug lub thickness ntawm dielectric txheej ntawm tag nrho pawg. Qhov zoo tshaj plaws, lub thickness ntawm txhua dielectric txheej yuav tsum tau mirrored nyob rau hauv ib tug zoo xws li cov txheej txheem yog mirrored.

Thaum lub thickness sib txawv, nws yuav nyuaj rau tau txais ib pab pawg neeg cov khoom uas yooj yim rau kev tsim khoom. Qee lub sij hawm vim muaj cov yam ntxwv xws li kav hlau txais xov kab, asymmetric stacking tej zaum yuav tsis muaj, vim hais tias qhov deb heev ntawm tus kav hlau txais xov kab thiab nws cov dav hlau siv yuav xav tau, tab sis thov nco ntsoov tshawb xyuas thiab tso tawm tag nrho ua ntej ua haujlwm. Lwm txoj kev xaiv. Thaum tsis sib npaug dielectric qhov sib txawv, cov neeg tsim khoom feem ntau yuav hais kom so lossis tso tseg tag nrho hneev taw thiab twist, thiab yog tias lawv tsis tuaj yeem tso tseg, lawv tuaj yeem tso tseg txoj haujlwm. Lawv tsis xav rov tsim dua ob peb cov khoom kim heev nrog cov txiaj ntsig qis, thiab tom qab ntawd thaum kawg tau txais cov khoom tsim nyog txaus kom tau raws li qhov kev txiav txim thawj zaug.

04
PCB thickness teeb meem

Hneev thiab twists yog cov teeb meem zoo tshaj plaws. Thaum koj pawg tsis sib npaug, muaj lwm qhov xwm txheej uas qee zaum ua rau muaj kev tsis sib haum xeeb hauv kev soj ntsuam zaum kawg - tag nrho PCB tuab ntawm cov haujlwm sib txawv ntawm lub rooj tsav xwm Circuit Court yuav hloov. Qhov xwm txheej no tshwm sim los ntawm kev saib xyuas me me thiab tsis tshua muaj tshwm sim, tab sis nws tuaj yeem tshwm sim yog tias koj qhov kev teeb tsa ib txwm muaj qhov tsis sib xws ntawm tooj liab ntawm ntau txheej hauv tib qhov chaw. Nws yog feem ntau pom ntawm cov laug cam uas siv tsawg kawg yog 2 ooj ntawm tooj liab thiab cov txheej txheem ntau heev. Dab tsi tshwm sim yog tias ib cheeb tsam ntawm lub rooj tsavxwm muaj ntau qhov chaw ntawm tooj liab-pob, thaum lwm qhov tsis muaj tooj liab. Thaum cov khaubncaws sab nraud povtseg ua ke, sab uas muaj tooj liab yog nias rau hauv ib lub thickness, thaum lub sab tsis muaj tooj liab los yog tooj liab-dawb yog nias.

Feem ntau lub rooj tsav xwm hauv Circuit Court siv ib nrab ooj lossis 1 ooj ntawm tooj liab yuav tsis cuam tshuam ntau, tab sis qhov hnyav dua tooj liab, qhov ntau dua qhov thickness poob. Piv txwv li, yog tias koj muaj 8 txheej ntawm 3 ooj tooj liab, thaj chaw uas muaj tooj liab sib zog tuaj yeem yooj yim poob qis dua tag nrho cov thickness kam rau ua. Txhawm rau tiv thaiv qhov no tshwm sim, nco ntsoov muab cov tooj liab sib npaug rau hauv tag nrho cov txheej txheej. Yog tias qhov no tsis zoo rau kev xav txog hluav taws xob lossis qhov hnyav, tsawg kawg ntxiv qee qhov plated los ntawm qhov ntawm lub teeb tooj liab txheej thiab xyuas kom muaj cov ntaub qhwv rau qhov ntawm txhua txheej. Cov qauv ntawm lub qhov / cov ntaub qhwv no yuav muab kev txhawb nqa txhua yam ntawm Y axis, yog li txo cov thickness poob.

05
Txim kev vam meej

Txawm tias thaum tsim thiab tso tawm ntau txheej PCBs, koj yuav tsum tau them sai sai rau ob qho tib si hluav taws xob kev ua tau zoo thiab cov qauv ntawm lub cev, txawm tias koj yuav tsum muaj kev cuam tshuam ntawm ob yam no kom ua tiav qhov tsim nyog thiab tsim tau tag nrho. Thaum hnyav ntau yam kev xaiv, nco ntsoov tias yog tias nws nyuaj los yog tsis tuaj yeem sau ib feem vim qhov deformation ntawm hneev thiab twisted cov ntaub ntawv, tus qauv tsim nrog cov khoom siv hluav taws xob zoo meej yog siv me ntsis. Sib npaug ntawm pawg thiab xyuam xim rau cov tooj liab faib rau txhua txheej. Cov kauj ruam no ua rau kom muaj peev xwm thaum kawg tau txais ib lub rooj tsav xwm Circuit Court uas yooj yim rau kev sib sau thiab nruab.