SMT reflow qhov cubtxheej txheem yuav tsum tau ob kawg ntawm Chip Cheebtsam solder vuam phaj yuav tsum tau ywj siab.Thaum lub ncoo txuas nrog hauv av xaim ntawm thaj chaw loj, txoj kev hla kev paving thiab txoj kev paving 45 ° yuav tsum nyiam dua.Cov hlau lead ntawm qhov loj hauv av xaim lossis kab hluav taws xob loj dua 0.5 hli, thiab qhov dav yog tsawg dua 0.4 hli;Cov hlau txuas nrog lub voj voos yuav tsum tau kos los ntawm qhov nruab nrab ntawm qhov ntev ntawm lub ncoo kom tsis txhob muaj lub kaum sab xis.
Saib daim duab (a) kom paub meej.
Daim duab (a)
Cov xov hlau nruab nrab ntawm SMD pads thiab cov hlau lead ntawm cov ntaub qhwv tau pom hauv daim duab (b).Daim duab yog daim duab sib txuas ntawm lub ncoo thiab cov ntawv luam tawm
Daim duab (b)
Kev taw qhia thiab cov duab ntawm cov hlau luam tawm:
(1) Cov ntawv luam tawm ntawm lub rooj tsavxwm yuav tsum luv luv, yog li ntawd, yog tias koj tuaj yeem siv qhov luv tshaj plaws, tsis txhob mus rau qhov nyuaj, ua raws li tuaj yeem yooj yim tsis ntau, luv tsis ntev.Nws yog ib qho kev pab zoo rau kev tswj xyuas zoo ntawm PCB Circuit Board nyob rau theem tom ntej.
(2) Cov kev taw qhia ntawm cov ntawv luam tawm yuav tsum tsis txhob muaj qhov nkhaus nkhaus thiab lub kaum ntse ntse, thiab lub kaum sab xis ntawm cov ntawv luam tawm yuav tsum tsis pub tsawg dua 90 °.Qhov no yog vim nws nyuaj rau corrode me me sab hauv cov ces kaum thaum ua daim hlau.Nyob rau ntawm cov ces kaum ntse heev, cov ntawv ci tuaj yeem yooj yim tev tawm lossis warp.Daim ntawv zoo tshaj plaws ntawm kev tig yog kev hloov maj mam, uas yog, sab hauv thiab sab nraud ntawm lub ces kaum yog qhov zoo tshaj plaws radians.
(3) Thaum cov hlau hla ntawm ob lub gaskets thiab tsis txuas nrog lawv, nws yuav tsum ua kom qhov siab tshaj plaws thiab sib npaug ntawm lawv;Ib yam li ntawd, qhov kev ncua deb ntawm cov xov hlau yuav tsum sib npaug thiab sib npaug thiab khaws cia rau qhov siab tshaj plaws.
Thaum txuas cov xov hlau ntawm PCB ncoo, qhov dav ntawm cov xov hlau yuav zoo ib yam li txoj kab uas hla ntawm lub ncoo thaum qhov kev ncua deb ntawm qhov nruab nrab ntawm lub ncoo yog tsawg dua li ntawm txoj kab uas hla ntawm cov ntaub qhwv D;Thaum qhov chaw nruab nrab ntawm cov ntaub qhwv ntau dua D, qhov dav ntawm cov hlau yuav tsum raug txo.Thaum muaj ntau tshaj 3 lub ncoo ntawm lub ncoo, qhov kev ncua deb ntawm cov conductors yuav tsum ntau dua 2D.
(4) Thaum sib txuas cov conductors ntawm PCB pads, qhov dav ntawm cov conductors yuav zoo ib yam li txoj kab uas hla ntawm lub ncoo thaum qhov kev ncua deb ntawm qhov nruab nrab ntawm cov ntaub so ntswg yog tsawg tshaj li ntawm sab nraud txoj kab uas hla D ntawm lub ncoo;Thaum qhov chaw nruab nrab ntawm cov ntaub qhwv ntau dua D, qhov dav ntawm cov hlau yuav tsum raug txo.Thaum muaj ntau tshaj 3 lub ncoo ntawm lub ncoo, qhov kev ncua deb ntawm cov conductors yuav tsum ntau dua 2D.
(5) Copper foil yuav tsum tau tshwj tseg rau cov xaim hauv av kom deb li deb tau.
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Post lub sij hawm: Jun-30-2021