1 Introduction

Ntawv luam tawm hauv Circuit Court board (PCB) teeb liab kev ncaj ncees tau yog lub ntsiab lus kub hauv xyoo tas los no. Muaj ntau cov ntaub ntawv tshawb fawb hauv tsev hais txog kev txheeb xyuas cov yam ntxwv cuam tshuam rau PCB teeb liab kev ncaj ncees, tab sis cov teeb liab poob kev sim Taw qhia rau lub xeev tam sim no ntawm cov thev naus laus zis kuj tsis tshua muaj.

Lub hauv paus ntawm PCB kis tau tus mob kab teeb liab poob yog tus neeg xyuas pib poob thiab dielectric poob ntawm cov khoom, thiab nws tseem cuam tshuam los ntawm cov yam ntxwv xws li tooj liab ntawv ci tsis kam, tooj liab ntawv ci roughness, hluav taws xob poob, impedance mismatch, thiab crosstalk. Nyob rau hauv cov saw hlau, cov kev lees paub ntawm tooj liab clad laminate (CCL) manufacturers thiab PCB nthuav qhia manufacturers siv dielectric tas li thiab dielectric poob; thaum cov ntsuas ntawm PCB nthuav qhia cov tuam txhab thiab cov khoom siv hluav taws xob feem ntau siv impedance thiab ntxig qhov poob, raws li pom hauv daim duab 1.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

Rau kev kub ceev PCB tsim thiab siv, yuav ua li cas kom sai thiab zoo ntsuas lub teeb liab poob ntawm PCB kis tau tus mob yog qhov tseem ceeb heev rau kev teeb tsa ntawm PCB tsim tsis, simulation debugging, thiab tswj cov txheej txheem ntau lawm.

2. Cov xwm txheej tam sim no ntawm PCB ntxig poob kev sim tshuab

PCB teeb liab kev ntsuas kev poob tam sim no siv hauv kev lag luam yog cais los ntawm cov cuab yeej siv, thiab tuaj yeem muab faib ua ob pawg: raws li lub sijhawm sau lossis raws li qhov ntau zaus. Lub sij hawm sau ntsuas ntsuas yog Lub Sijhawm Domain Reflectometry (TDR) lossis lub sijhawm sau cov ntsuas ntsuas (TImeDomain Transmission, TDT); qhov ntsuas qhov ntsuas zaus yog Vector Network Analyzer (VNA). Nyob rau hauv IPC-TM650 xeem specification, tsib txoj kev xeem tau pom zoo rau PCB teeb liab tsis kuaj: zaus domain method, zoo bandwidth txoj kev, lub hauv paus mem tes zog txoj kev, luv pulse propagation txoj kev, ib leeg-kawg TDR sib txawv insertion poob txoj kev.

2.1 Zaus domain method

Txoj Kev Zaus Domain feem ntau yog siv lub vector network analyzer los ntsuas qhov S-tsis ntawm cov kab sib kis, ncaj qha nyeem cov nqi nkag, thiab tom qab ntawd siv qhov kev sib haum xeeb ntawm qhov nruab nrab qhov kev poob qis hauv qhov ntau zaus (xws li 1 GHz ~ 5 GHz) Ntsuas qhov dhau / tsis ua haujlwm ntawm lub rooj tsavxwm.

Qhov sib txawv ntawm qhov ntsuas qhov tseeb ntawm qhov zaus domain method mas yog los ntawm txoj kev calibration. Raws li cov kev sib txawv calibration, nws tuaj yeem muab faib ua SLOT (Short-Line-Open-Thru), MulTI-Line TRL (Thru-Reflect-Line) thiab Ecal (Electronic calibraTIion) electronic calibration method.

SLOT feem ntau suav hais tias yog txoj kev ntsuas tus qauv [5]. Tus qauv calibration muaj 12 qhov yuam kev. Qhov tseeb calibration ntawm SLOT txoj kev yog txiav txim los ntawm cov calibration qhov chaw. Lub high-precision calibration qhov chaw yog muab los ntawm cov khoom ntsuas manufacturers, tab sis cov calibration qhov chaw yog kim, thiab feem ntau tsuas yog haum rau coaxial ib puag ncig, calibration yog lub sij hawm-siv thiab nce geometrically raws li tus naj npawb ntawm cov ntsuas terminals nce.

Txoj kev MulTI-Line TRL feem ntau yog siv rau kev ntsuas tsis yog coaxial calibration [6]. Raws li cov khoom siv ntawm cov kab sib kis tau siv los ntawm tus neeg siv thiab qhov kev xeem zaus, TRL calibration qhov chaw yog tsim thiab tsim, raws li qhia hauv daim duab 2. Txawm hais tias Multi-Line TRL yog yooj yim rau kev tsim thiab tsim dua SLOT, lub sij hawm calibration ntawm Multi-Line TRL txoj kev kuj nce geometrically nrog qhov nce ntawm cov lej ntsuas terminals.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

Yuav kom daws tau qhov teeb meem ntawm lub sij hawm siv calibration, ntsuas khoom manufacturers tau qhia Ecal electronic calibration method [7]. Ecal yog tus qauv kis tau tus mob. Qhov tseeb calibration yog tsuas yog txiav txim los ntawm tus thawj calibration qhov chaw. Nyob rau tib lub sijhawm, kev ruaj ntseg ntawm kev kuaj cable thiab qhov sib npaug ntawm cov khoom siv sib tw tau sim. Lub interpolation algorithm ntawm kev ua tau zoo thiab kev xeem zaus kuj muaj feem cuam tshuam rau qhov kev xeem raug. Feem ntau, siv cov khoom siv hluav taws xob ntsuas hluav taws xob los ntsuas qhov siv qhov chaw mus rau qhov kawg ntawm qhov ntsuas kab, thiab tom qab ntawd siv txoj kev de-embedding los them cov cable ntev ntawm lub fixture. Raws li pom hauv daim duab 3.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

Txhawm rau kom tau txais qhov poob ntawm qhov sib txawv ntawm cov kab sib txuas ua piv txwv, qhov kev sib piv ntawm peb txoj kev ntsuas ntsuas tau qhia hauv Table 1.

2.2 Txoj kev siv bandwidth zoo

Siv Tau Bandwidth (EBW) yog qhov kev ntsuas zoo ntawm kev sib kis kab poob α hauv kev txiav txim siab nruj. Nws tsis tuaj yeem muab tus nqi ntau ntawm qhov poob, tab sis nws muab qhov ntsuas hu ua EBW. Txoj kev siv bandwidth zoo yog xa cov kauj ruam teeb liab nrog lub sijhawm tshwj xeeb nce mus rau cov kab sib kis los ntawm TDR, ntsuas qhov siab tshaj plaws ntawm qhov nce lub sij hawm tom qab TDR ntsuas thiab DUT txuas nrog, thiab txiav txim siab tias nws yog qhov poob, hauv MV. /s. Ntau precisely, Qhov nws txiav txim siab yog ib tug txheeb ze ntawm tag nrho cov poob qhov tseem ceeb, uas yuav siv tau los txheeb xyuas cov kev hloov nyob rau hauv kev sib kis kab poob los ntawm nto rau nto los yog txheej rau txheej [8]. Txij li qhov siab tshaj qhov nqes hav tuaj yeem ntsuas ncaj qha los ntawm qhov ntsuas, txoj kev siv bandwidth zoo feem ntau yog siv rau kev sim ntau lawm ntawm cov ntawv luam tawm hauv Circuit Court. Daim duab schematic ntawm EBW xeem yog qhia hauv daim duab 4.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

2.3 Hauv paus mem tes zog txoj kev

Lub hauv paus ImPulse Energy (RIE) feem ntau siv TDR cov cuab yeej kom tau txais TDR waveforms ntawm cov ntaub ntawv poob thiab cov kab sib kis, thiab tom qab ntawd ua cov teeb liab ua rau TDR waveforms. Cov txheej txheem kev xeem RIE tau pom hauv daim duab 5:

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

2.4 Short pulse propagation method

Txoj kev luv luv pulse propagation (Short Pulse Propagation, hu ua SPP) txoj cai ntsuas yog ntsuas ob txoj kab sib txuas ntawm qhov ntev sib txawv, xws li 30 hli thiab 100 hli, thiab rho tawm cov parameter attenuation coefficient thiab theem los ntawm kev ntsuas qhov sib txawv ntawm ob. kis kab mob ntev. Tsis tu ncua, raws li pom hauv daim duab 6. Kev siv txoj kev no tuaj yeem txo qhov cuam tshuam ntawm cov khoom sib txuas, cables, sojntsuam, thiab oscilloscope raug. Yog tias cov cuab yeej ua haujlwm siab TDR thiab IFN (Impulse Forming Network) tau siv, qhov ntsuas zaus tuaj yeem siab li 40 GHz.

2.5 Ib leeg-kawg TDR qhov sib txawv ntawm qhov tsis sib xws

Tib-Ended TDR rau Differential Insertion Loss (SET2DIL) yog qhov sib txawv ntawm qhov sib txawv ntawm qhov tsis sib xws siv 4-chaw nres nkoj VNA. Txoj kev no siv ob-chaw nres nkoj TDR cov cuab yeej xa cov TDR cov kauj ruam teb rau cov kab sib txawv, qhov kawg ntawm cov kab sib txawv ntawm cov kab sib txawv yog luv luv, raws li pom hauv daim duab 7. Qhov kev ntsuas zaus ntau ntawm SET2DIL txoj kev yog 2 GHz ~ 12 GHz, thiab qhov ntsuas qhov tseeb yog feem ntau cuam tshuam los ntawm qhov tsis sib haum xeeb ncua ntawm qhov ntsuas kab thiab qhov impedance tsis sib haum ntawm DUT. Qhov kom zoo dua ntawm SET2DIL txoj kev yog tias tsis tas yuav siv qhov kim 4-chaw nres nkoj VNA thiab nws cov calibration qhov chaw. Qhov ntev ntawm cov kab sib kis ntawm qhov kev sim no tsuas yog ib nrab ntawm VNA txoj kev. Lub calibration ib feem muaj ib tug yooj yim qauv thiab lub sij hawm calibration yog heev txo. Nws yog heev haum rau PCB manufacturing. Batch test, raws li qhia hauv daim duab 8.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

3 Cov khoom siv ntsuas thiab ntsuas ntsuas

SET2DIL test board, SPP test board thiab Multi-Line TRL test board tau siv CCL nrog dielectric tas li ntawm 3.8, dielectric poob ntawm 0.008, thiab RTF tooj liab ntawv ci; Cov khoom siv kuaj yog DSA8300 sampling oscilloscope thiab E5071C vector network analyzer; Qhov sib txawv ntawm qhov sib txawv ntawm qhov poob ntawm txhua txoj kev Cov txiaj ntsig tau pom nyob rau hauv Table 2.

Kev soj ntsuam ntawm cov yam ntxwv cuam tshuam ntawm cov teeb liab kev ntseeg siab ntawm PCB Printed Circuit Board

4 Xaus

Cov kab lus no feem ntau qhia txog ntau lub PCB kis tau tus kab teeb liab kev ntsuas kev ntsuas tam sim no siv hauv kev lag luam. Vim yog cov kev sim sib txawv siv, qhov ntsuas qhov ntsuas qhov poob qhov sib txawv, thiab cov txiaj ntsig tsis tuaj yeem sib piv ncaj qha kab rov tav. Yog li ntawd, qhov tsim nyog lub teeb liab poob kev sim tshuab yuav tsum raug xaiv raws li qhov zoo thiab kev txwv ntawm ntau yam kev siv, thiab ua ke nrog lawv tus kheej xav tau.