SMD (Nto Mounted Devices) hauv lus Askiv txhais tau tias "nto mounted device". SMD Cheebtsam yog cov sijhawm me me hauv qhov loj me thiab qhov hnyav dua li qub, vim tias qhov no, ntau dua ntawm lawv cov paj huam luam tawm ntawm cov khoom siv hluav taws xob ntawm cov khoom siv tau ua tiav. Nyob rau hauv peb lub sij hawm, electronics yog tsim nyob rau hauv ib tug zoo kawg li pace, ib tug ntawm cov lus qhia yog kom txo tau lub zuag qhia tag nrho qhov ntev thiab qhov hnyav ntawm cov khoom siv. SMD Cheebtsam - vim lawv qhov loj me, tus nqi qis, zoo siab - tau dhau los ua qhov dav thiab tau hloov pauv cov khoom qub nrog cov hlau lead.
Daim duab hauv qab no qhia txog SMD resistors tso rau ntawm PCB.
Nws tuaj yeem pom tau tias, vim qhov me me ntawm cov ntsiab lus, qhov siab mounting ceev tau tiav. Cov khoom qub tau muab tso rau hauv qhov tshwj xeeb hauv lub rooj tsavxwm, thiab SMD resistors yog soldered rau kev sib cuag lem (spots) nyob rau saum npoo ntawm lub rooj tsavxwm luam tawm, uas kuj yooj yim rau kev txhim kho thiab sib dhos ntawm cov khoom siv hluav taws xob. Ua tsaug rau qhov ua tau ntawm qhov chaw txuas ntawm cov khoom siv hauv xov tooj cua, nws tau dhau los ua cov ntawv luam tawm tsis yog ob sab, tab sis kuj muaj ntau txheej, zoo li lub ncuav mog qab zib.
Hauv kev tsim khoom, soldering ntawm SMD Cheebtsam yog ua los ntawm cov hauv qab no: ib qho tshwj xeeb soldering thermal muab tshuaj txhuam (flux tov nrog solder hmoov) yog siv rau kev sib cuag ntawm lub rooj tsavxwm, tom qab uas tus neeg hlau tso cov khoom hauv qhov chaw zoo, suav nrog SMD resistors. Cov khoom siv lo rau cov tshuaj txhuam hniav, tom qab ntawd lub rooj tsavxwm tau muab tso rau hauv qhov cub tshwj xeeb, qhov chaw uas nws tau rhuab mus rau qhov ntsuas kub uas yuav tsum tau ua, thaum lub solder nyob rau hauv paste melts thiab flux evaporates. Yog li, cov ntsiab lus poob rau hauv qhov chaw. Tom qab ntawd, lub rooj tsavxwm luam tawm raug tshem tawm ntawm qhov cub thiab txias.
Y Yuav kom cov khoom siv SMD nyob hauv tsev, koj yuav xav tau cov cuab yeej hauv qab no: tweezers, awl, hlau cutters, iav magnifying, ib lub koob txhaj tshuaj nrog ib rab koob tuab, cov hlau nplaum nrog lub hau nyias, cua kub soldering. chaw nres tsheb. Ntawm cov consumables, solder, kua flux yog xav tau. Nws yog advisable, ntawm chav kawm, siv ib tug soldering chaw nres tsheb, tab sis yog hais tias koj tsis muaj ib tug, koj yuav tau txais los ntawm ib tug soldering hlau. Thaum soldering, qhov tseem ceeb tshaj plaws yog tiv thaiv overheating ntawm cov khoom thiab cov ntawv luam tawm Circuit Board. Txhawm rau kom cov ntsiab lus tsis txav mus thiab tsis lo rau qhov kawg ntawm cov hlau soldering, lawv yuav tsum tau nias rau ntawm lub rooj tsavxwm nrog ib rab koob.
SMD resistors tau nthuav tawm nyob rau hauv ntau qhov sib txawv ntawm tus nqi nominal: los ntawm ib Ohm mus rau peb caug megaOhm. Kev khiav hauj lwm kub ntawm xws li resistors ranges ntawm -550 ° C rau + 1250 ° C. Lub zog ntawm SMD resistors ncav cuag 1W. Raws li lub zog nce, tag nrho qhov ntev nce. Piv txwv li, 0.05W SMD resistors yog 0.60.30.23mm, thiab 1W yog 6.353.20.55mm.
Lub cim ntawm cov resistors yog peb hom: nrog peb tus lej, nrog plaub tus lej thiab nrog peb lub cim:
- Thawj ob tus lej qhia tus nqi ntawm cov resistor hauv ohms, thiab qhov kawg - tus lej ntawm xoom. Piv txwv li, lub cim ntawm tus resistor 102 txhais tau tias 1000 ohms lossis 1k ohms.
- Thawj peb tus lej ntawm tus resistor qhia tus nqi nominal hauv ohms, thiab tus lej kawg qhia tus lej ntawm xoom. Piv txwv li, lub cim ntawm 5302 resistor txhais tau tias 53 kOhm.
- Thawj ob lub cim ntawm tus resistor qhia tus nqi nominal hauv ohms, coj los ntawm lub rooj saum toj no, thiab tus cim kawg qhia tus nqi ntawm tus lej: S=10-2; R=10-1; B=10; C=102; D=103; E=104; F=105. Piv txwv li, lub cim ntawm 11C resistor txhais tau tias 12.7 kOhm.
