Dab tsi yog qhov dhau los ntawm PCB thiab vim li cas nws thiaj tseem ceeb rau luam tawm hauv Circuit Court board? Ib lub PCB xav tau los ntawm lub qhov lossis qhov av kom txuas nws cov khaubncaws sab nraud povtseg. Understanding the standard through-hole sizes used by PCB manufacturers can help you design boards to meet common bit sizes.

Txuj los ntawm qhov loj me

Cov tuam txhab tsim khoom PCB muaj lawv tus kheej txheej txheem qhov ntau thiab tsawg los xaiv los ntawm qhov drilling qhov, tab sis lawv feem ntau tuaj yeem siv txhua qhov loj me me. Feem ntau, cov tuam txhab tsim khoom lag luam PCB tuaj yeem ua txoj kab uas hla ntawm PCB los ntawm qhov me me li 0.15 hli, piv rau qhov loj me ntawm 0.6 hli.

PCB los ntawm qhov loj me me xav tau

Nov yog qhov kev tshawb fawb tob ntawm qhov xav tau loj.

PCB los ntawm qhov loj me

Qhov loj ntawm PCB los ntawm lub qhov tuaj yeem sib txawv nyob ntawm nws qhov chaw nyob, siv, thiab lwm yam, uas yog vim li cas txhua lub chaw tsim khoom PCB muab ntau qhov PCB me me. Most manufacturers can make holes as small as 0.15 mm or larger holes of 1 mm or larger. Thaum txiav txim siab qhov loj ntawm lub qhov yuav tsum tau ua, koj kuj yuav tsum xav txog lub nplhaib lossis tooj liab ncoo ncig lub qhov, uas yuav tsim.

How do you calculate rings? The ideal ring is equal to the sum of the diameter of the copper pad minus the diameter of the drill hole divided by 2, which gives the rig the best chance of hitting the center of the pad for optimal connectivity.

Txuj los ntawm qhov loj me

Tsis tas yuav muaj tus txheej txheem PCB dhau los-qhov loj hauv PCB tsim khoom, raws li tus txheej txheem PCB dhau los ntawm qhov loj feem ntau txawv ntawm cov chaw tsim khoom mus rau PCB chaw tsim khoom. Txawm li cas los xij, ntau lub tuam txhab PCB nyiam siv ntau qhov me me, uas lawv tuaj yeem xa mus rau raws li tus qauv PCB me me. Ib qho ntawm qhov ntau thiab tsawg yog 0.6 hli, tab sis 0.2 hli thiab 0.3 hli kuj tseem siv.

Type of PCB through hole

Koj tuaj yeem siv txhua tus qauv dhau los-qhov loj kom tsim ntau hom PCB los ntawm qhov, nyob ntawm txheej, tsim, tsim, thiab lub hom phiaj ntawm PCB. Peb hom PCB feem ntau dhau los ntawm qhov yog:

Plated los ntawm qhov

Electroplated through-hole (PTH) yog hla qhov uas khiav hla txhua txheej ntawm PCB los txuas cov txheej saum toj thiab hauv qab. Koj yuav tsum muaj peev xwm pom PTH los ntawm ib kawg ntawm PCB mus rau lwm qhov. PTH tej zaum yuav plated lossis tsis plated. Tsis plated los ntawm qhov tsis ua hluav taws xob, qhov plated los ntawm qhov yog electroplated, uas txhais tau tias lawv ua hluav taws xob hauv txhua txheej ntawm PCB.

Qhov muag tsis pom qhov

Blind holes connect the outer (top or bottom) layers of the PCB to one or more inner layers, but do not completely drill through the board. Precise drilling of blind holes can be challenging, so they are typically more expensive to manufacture than PTH.

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Embedded holes can also increase the cost of PCB because they are difficult to manufacture. The holes are located in the inner layer of the PCB to connect two or more inner layers. Koj tsis tuaj yeem pom cov khoom faus rau ntawm PCB txheej txheej.

Yam yuav tau xav txog

Muaj ob peb yam los txiav txim siab thaum tsim PCB. Ua ntej, koj yuav tsum paub dab tsi piv piv hauv PCB tsim. The aspect ratio is the PCB thickness relative to the diameter of the through hole, which determines the reliability of the copper plating on the PCB. The higher the ratio, the more difficult it is to obtain reliable plating, which affects the type of hole and plating method you choose.

Embedded lossis dig muag qhov tuaj yeem ua haujlwm rau koj PCB zoo dua nrog qhov sib piv ntawm 15: 1, thaum PTH tuaj yeem ua haujlwm tau zoo nrog qhov sib piv qis ntawm 2: 1. Koj xaiv qhov tuab ntawm PCB tooj liab li cas? Usually, through holes in the outer layer (e.g., through holes) require a thicker layer of copper than the buried through holes inside. Qhov hluav taws xob siv los ntawm PCB kuj cuam tshuam rau qhov tuab ntawm tooj liab. High voltage applications typically require thicker PCB copper than low voltage applications.

By filling program

Sometimes PCB through-holes need to be filled, for example to reduce the risk of trapping air or increase electrical conductivity. Some common ways to fill through holes include:

Los ntawm lub tsev pheeb suab ntaub

Lub tsev pheeb suab los ntawm qhov tsim cov txheej txheem txheej txheej hla PCB los ntawm lub qhov ntau dua li ua kom lub qhov nrog cov khoom siv. This can be a quick, easy and cost-effective option to cover the through-holes, but the tent-style through-holes may reopen over time.

Los ntawm kev thaiv

Cov txheej txheem txhawm rau txhawm rau txhawm rau txhaws lub qhov nrog cov khoom siv tsis zoo thiab muab nws npog nrog lub npog ntsej muag. Through-hole clogging also covers the ring and does not produce a smooth, glossy surface.

Los ntawm kev sau

Los ntawm qhov-qhov txhaws siv cov yas los tsim lub qhov tso tas mus li. A through-hole fill is a common through-hole fill in which the manufacturer fills the through-hole with conductive material, coats the surface with copper, and then trims the surface. This process can route signals to other areas of the PCB.

PCB los ntawm qhov siv plating daim ntawv thov

Cov tuam txhab tsim khoom tuaj yeem siv ntau yam txheej txheem sib txawv los thov PCB los ntawm qhov-plating kom ntseeg tau tias nws ua tau zoo. One common method is to use a low viscosity ink that covers the inside of the through-hole to form a conductive layer. Then through the heat curing process to bond the ink.

Lwm txoj hauv kev yog electroplating, nyob rau hauv uas PCB nkag mus rau hauv qhov da dej electroplating. Hauv cov txheej txheem no, tooj liab npog cov phab ntsa ntawm txhua PCB los ntawm qhov, ua rau muaj qhov tuab ntawm cov khoom siv. Txoj hauv kev no zoo li yuav siv sijhawm ntev dua thiab kim dua cov txheej txheem inking, tab sis nws tseem tuaj yeem tsim cov txheej txheej txhim khu kev ntseeg ntau dua.

Sequential drilling blind drilling and deep drilling

PCBS nrog qhov muag qhov muag tuaj yeem tsim ua ob txoj hauv kev. This can be done by laser drilling or by a method called continuous layer construction. Using the sequential construction method, pairs of layers can be drilled and electroplated before bonding is applied. Because they have holes at both ends, electroplating is easy to penetrate for chemical coatings. It also allows blind holes to be designed in such a way that they can pass through multiple layers.

Lub peev xwm los ua ke cov kev sib raug zoo tsim nyog, kev sib dhos thiab txheej txheej ua rau nws muaj peev xwm los tsim ntau yam qhov muag tsis pom. Nws txhua yam nyob ntawm seb qhov qhov muag tsis pom tuaj yeem hla dhau txawm tias txheej los ntawm txheej txheej.

Simultaneous deep drilling or reverse drilling is the process of removing any unused copper drum residue from the through hole. Qhov no feem ntau tshwm sim thaum cov cim qhia nrawm tau cuam tshuam thaum lawv dhau los ntawm cov raj tooj liab ntawm cov txheej PCB. Yog tias siv cov txheej txheem teeb tsa ua rau muaj kev hloov pauv mus ntev, yuav muaj qhov txawv txav ntau.

PCB nam piv tau txhais raws li qhov sib piv ntawm phaj tuab rau txoj kab uas hla ntawm lub qhov dej. Qhov muag tsis pom qhov xav tau qhov sib piv ntawm 1 txog 1 lossis ntau dua.

Thaum kev sib sib zog nqus tau ua tiav, qhov tob ntawm lub qhov yog txhais los ntawm teeb tsa ib khub ntawm qhov uas hais qhia pib thiab xaus txheej los ntawm ib sab ntawm lub rooj tsavxwm. Qhov taub me ntsis rau kev sib sib zog nqus yog xam los ntawm cov qauv hauv qab no:

Sab nraub qaum qhov loj = Qhov/qhov ncoo qhov loj + 2 x Tsim cov cai Rov qab laum loj loj dhau

PCB overinductance calculator

PCB dhau los-qhov inductance nyob ntawm ntau yam, suav nrog hauv qhov loj me, lub nplhaib loj, qhov sib piv, thiab qhov raug qhov tseeb. Koj tuaj yeem nrhiav cov laij lej online los pab koj suav qhov PCB raug raws li qhov loj koj xav siv.