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Kev soj ntsuam ntawm Back Drilling Technology hauv Kev Kub Ceev PCB Tsim
2024-04-08 17:37:03 dr hab
Vim li cas peb yuav tsum ua Backdrill tsim?
Ua ntej, cov khoom ntawm kev sib txuas ceev ceev yog:
① Xa cov nti kawg ( ntim thiab PCB ntawm)
② Sub daim npav PCB thaiv
③ Sub card connector
④ Backboard PCB thaiv
⑤ Rov qab sub daim npav txuas
⑥ Sab nraud sub daim npav PCB thaiv
⑦ AC coupling capacitance
⑧ Txais nti ( ntim thiab PCB ntawm)
Kev sib txuas ntawm cov teeb liab ceev ceev ntawm cov khoom siv hluav taws xob yog qhov nyuaj, thiab cov teeb meem tsis sib haum xeeb feem ntau tshwm sim ntawm qhov sib txawv ntawm cov ntsiab lus sib txuas, ua rau cov teeb liab tawm.
Common impedance discontinuity cov ntsiab lus nyob rau hauv high-speed interconnect links:
(1) Chip ntim: Feem ntau, PCB thaiv qhov dav hauv cov ntim ntim khoom ntim yog nqaim dua li ntawm PCB li niaj zaus, ua rau kev tswj tsis tau yooj yim;
(2) PCB ntawm: PCB ntawm feem ntau yog cov teebmeem capacitive nrog cov yam ntxwv impedance tsawg, thiab nws yuav tsum tau tsom thiab optimized tshaj hauv PCB tsim;
(3) Connector: Tus tsim ntawm tooj liab interconnect txuas nyob rau hauv lub connector yog cuam tshuam los ntawm ob qho tib si mechanical kev ntseeg tau thiab hluav taws xob kev ua tau zoo, yog li ntawd yuav tsum nrhiav kev sib npaug ntawm ob.
PCB ntawm feem ntau yog tsim los ntawm qhov (los ntawm qhov saum npoo mus rau hauv qab txheej). Thaum cov kab PCB txuas rau ntawm txoj kab yog dhau los ze dua rau txheej txheej saum toj kawg nkaus, "stub" bifurcation yuav tshwm sim ntawm qhov sib txuas ntawm PCB, ua rau muaj kev cuam tshuam cov teeb liab thiab cuam tshuam cov teeb liab zoo. Qhov kev cuam tshuam no muaj kev cuam tshuam ntau dua rau cov teeb liab ntawm qhov nrawm dua.
Troduction rau Backdrill Processing Methods
Rov qab drilling tshuab yog hais txog kev siv qhov tob tswj txoj kev drilling, siv cov txheej txheem thib ob txhawm rau tho tawm Stub qhov phab ntsa ntawm qhov txuas lossis teeb liab ntawm.
Raws li pom nyob rau hauv daim duab hauv qab no, tom qab lub qhov dhau los ntawm lub qhov yog tsim, qhov ntau Stub ntawm PCB los ntawm lub qhov yog tshem tawm los ntawm theem nrab drilling los ntawm "sab nraum qab". Tau kawg, txoj kab uas hla ntawm lub backdrill me ntsis yuav tsum loj dua qhov loj ntawm lub qhov, thiab qhov tob tob ntawm cov txheej txheem drilling yuav tsum yog raws li lub hauv paus ntsiab lus ntawm "tsis ua rau kev sib txuas ntawm PCB qhov thiab cov xaim", xyuas kom meej. hais tias "qhov seem ntawm qhov ntev yog me npaum li sai tau", uas yog hu ua "qhov tob tswj qhov drilling".
Schematic daim duab ntawm dhau-qhov BackDrill seem
Cov saum toj no yog daim duab schematic ntawm dhau-qhov BackDrill seem. Sab laug yog lub teeb liab ib txwm dhau los ntawm lub qhov, ntawm sab xis yog daim duab kos duab ntawm lub qhov los ntawm qhov tom qab BackDrill, qhia txog qhov drilling los ntawm cov txheej hauv qab mus rau qhov teeb liab txheej uas cov kab nyob.
Rov qab drilling tshuab tuaj yeem tshem tawm cov kab mob parasitic capacitance tshwm sim los ntawm lub qhov phab ntsa stubs, kom ntseeg tau qhov sib xws ntawm cov xaim thiab cov impedance ntawm qhov kev sib txuas ntawm cov channel txuas, txo cov teeb liab kev xav, thiab yog li txhim kho cov teeb liab zoo.
Backdrill yog tam sim no cov cuab yeej siv tau zoo tshaj plaws uas yog qhov zoo tshaj plaws rau kev txhim kho kev sib kis ntawm cov channel. Kev siv cov cuab yeej siv rov qab drilling yuav ua rau tus nqi ntawm PCB ntau lawm rau qee yam.
Kev faib tawm ntawm Single Board Back Drilling
Back drilling yog muaj 2 hom: ib sab rov qab drilling thiab ob sab rov qab drilling.
Ib leeg ib sab drilling tuaj yeem muab faib ua rov qab drilling los ntawm sab saum toj lossis hauv qab. Tus PIN qhov ntawm lub connector plug pin tuaj yeem tsuas yog rov qab los ntawm sab nraud mus rau lub ntsej muag qhov chaw txuas. Thaum cov teeb liab ceev ceev tau teeb tsa ntawm ob sab saum toj thiab hauv qab ntawm PCB, yuav tsum tau muab ob npaug rau sab nraub qaum.
Qhov zoo ntawm rov qab drilling
1) Txo cov suab nrov cuam tshuam;
2) Txhim kho teeb liab kev ncaj ncees;
3) Hauv zos board thickness txo;
4) Txo kev siv faus / qhov muag tsis pom los ntawm kev txo qhov nyuaj ntawm PCB ntau lawm.
Lub luag haujlwm ntawm rov qab drilling yog dab tsi?
Kev ua haujlwm ntawm rov qab drilling yog txhawm rau txhawm rau hauv qhov-qhov seem uas tsis muaj kev sib txuas lossis kev sib kis ua haujlwm kom tsis txhob muaj kev cuam tshuam, tawg, ncua, thiab lwm yam hauv cov teeb liab ceev ceev.
Rov qab txheej txheem drilling
a. Muaj qhov chaw tso rau ntawm PCB, uas yog siv rau thawj qhov chaw drilling thiab thawj qhov drilling ntawm PCB;
b. Electrolate PCB tom qab thawj lub qhov drilling, thiab zaj duab xis qhuav kaw lub qhov chaw ua ntej electroplating;
c. Tsim cov qauv txheej txheej ntawm electroplated PCB;
d. Ua qauv electroplating ntawm PCB tom qab tsim cov txheej txheej txheej;
e. Siv qhov chaw qhov chaw uas tau siv los ntawm thawj qhov drilling rau rov qab drilling qhov chaw, thiab siv lub laum hniav rau rov qab drilling;
f. Ntxuav lub qhov rov qab drilled nrog dej kom tshem tawm cov seem seem hauv qhov drilling.