Cov cuab yeej tsoos rau kev debugging PCB suav nrog: lub sij hawm sau oscilloscope, TDR (time domain reflectometry) oscilloscope, logic analyzer, thiab zaus domain spectrum analyzer thiab lwm yam khoom siv, tab sis cov txheej txheem no tsis tuaj yeem muab qhov kev xav ntawm tag nrho cov ntaub ntawv ntawm PCB pawg thawj coj saib. cov ntaub ntawv. PCB board tseem hu ua cov ntawv luam tawm Circuit Board, luam tawm Circuit Board, luam tawm Circuit Board luv luv, PCB (printed circuit board) los yog PWB (printed wiring board) luv luv, siv insulating board ua cov khoom siv hauv paus, txiav rau hauv ib qho loj, thiab yam tsawg kawg txuas Ib qho qauv nrog qhov (xws li cov khoom sib txuas, qhov txuas txuas, qhov metallized, thiab lwm yam) yog siv los hloov lub chassis ntawm cov khoom siv hluav taws xob ntawm cov cuab yeej dhau los thiab paub txog kev sib tshuam ntawm cov khoom siv hluav taws xob. Vim tias lub rooj tsavxwm no yog tsim los siv hluav taws xob luam ntawv, nws hu ua “luam tawm” Circuit Board. Nws tsis raug hu ua “luam tawm Circuit board” ua “luam Circuit Court” vim tias tsis muaj “cov khoom luam tawm” tab sis tsuas yog xaim ntawm lub rooj tsav xwm luam tawm.

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Emscan electromagnetic compatibility scanning system siv patented array kav hlau txais xov tshuab thiab hluav taws xob hloov tshuab, uas tuaj yeem ntsuas qhov tam sim no ntawm PCB ntawm kev kub ceev. Tus yuam sij rau Emscan yog siv lub kav hlau txais xov patented array los ntsuas qhov ze-tsav hluav taws xob ntawm lub chaw ua haujlwm PCB tso rau ntawm lub tshuab luam ntawv. Cov kav hlau txais xov no muaj 40 x 32 (1280) me me H-tsav sojntsuam, uas tau kos rau hauv 8-txheej Circuit Court board, thiab txheej tiv thaiv tau ntxiv rau lub rooj tsav xwm hauv Circuit Court kom tso PCB hauv kev sim. Cov txiaj ntsig ntawm spectrum scanning tuaj yeem ua rau peb nkag siab zoo ntawm cov spectrum tsim los ntawm EUT: pes tsawg zaus muaj, thiab qhov kwv yees qhov loj ntawm txhua qhov feem ntau zaus.

Tag nrho band scan

Kev tsim ntawm PCB pawg thawj coj saib yog ua raws li daim duab kos duab hauv Circuit Court kom paub txog cov haujlwm uas yuav tsum tau ua los ntawm tus tsim qauv Circuit Court. Kev tsim ntawm lub rooj tsavxwm luam tawm feem ntau yog hais txog kev tsim qauv tsim, uas yuav tsum tau xav txog ntau yam xws li kev teeb tsa ntawm kev sib txuas sab nraud, kev ua kom zoo ntawm cov khoom siv hluav taws xob sab hauv, kev ua kom zoo ntawm cov hlau sib txuas thiab los ntawm qhov, kev tiv thaiv electromagnetic, thiab kub dissipation. Kev tsim qauv zoo heev tuaj yeem txuag tau tus nqi tsim khoom thiab ua tiav kev ua haujlwm zoo hauv Circuit Court thiab kev ua haujlwm kub dissipation. Kev tsim qauv yooj yim tuaj yeem ua tiav los ntawm tes, thaum tsim qauv tsim yuav tsum tau ua tiav nrog kev pab ntawm lub khoos phis tawj-pab tsim.

Thaum ua cov spectrum/spatial scanning muaj nuj nqi, tso lub PCB ua hauj lwm rau lub scanner. Lub PCB tau muab faib ua 7.6mm × 7.6mm daim phiaj los ntawm daim phiaj ntawm lub tshuab luam ntawv (txhua daim phiaj muaj H-field sojntsuam), thiab ua haujlwm Tom qab kuaj xyuas tag nrho cov zaus band ntawm txhua qhov kev sojntsuam (qhov ntau zaus tuaj yeem yog los ntawm 10kHz-3GHz) , Emscan thaum kawg muab ob daim duab, uas yog lub synthesized spectrogram (Daim duab 1) thiab lub synthesized chaw daim ntawv qhia (Daim duab 2).

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Spectrum/spatial scanning tau txais tag nrho cov ntaub ntawv spectrum ntawm txhua qhov kev sojntsuam hauv tag nrho cheeb tsam scanning. Tom qab ua qhov spectrum / spatial scan, koj tuaj yeem tau txais cov ntaub ntawv hluav taws xob hluav taws xob ntawm txhua zaus ntawm txhua qhov chaw. Koj tuaj yeem xav txog cov ntaub ntawv spectrum/spatial scan hauv daim duab 1 thiab daim duab 2 raws li ib pawg ntawm spatial scan cov ntaub ntawv lossis ib pawg ntawm spectrum Scan cov ntaub ntawv. koj tuaj yeem:

1. Saib daim ntawv qhia spatial faib ntawm qhov taw qhia zaus (ib lossis ntau zaus) ib yam li saib cov txiaj ntsig spatial scanning, raws li pom hauv daim duab 3.

2. Saib cov spectrogram ntawm lub cev qhov chaw taw qhia (ib lossis ntau daim phiaj) ib yam li saib cov spectrum scan tshwm sim.

Daim duab spatial faib ntau yam hauv daim duab 3 yog daim duab spatial plab plab ntawm cov ntsiab lus zaus pom los ntawm cov ntsiab lus zaus. Nws yog tau los ntawm kev qhia qhov zaus taw tes nrog × nyob rau hauv lub Uppermost spectrogram nyob rau hauv daim duab. Koj tuaj yeem hais qhia qhov zaus los saib qhov kev faib tawm ntawm txhua qhov zaus, lossis koj tuaj yeem qhia ntau zaus cov ntsiab lus, piv txwv li, qhia tag nrho cov ntsiab lus sib haum xeeb ntawm 83M kom pom tag nrho cov spectrogram.

Hauv daim duab spectrogram hauv daim duab 4, qhov grey yog tag nrho cov spectrogram, thiab xiav feem yog cov spectrogram ntawm qhov chaw teev tseg. Los ntawm kev qhia lub cev qhov chaw ntawm PCB nrog ×, muab piv rau spectrogram (xiav) thiab tag nrho spectrogram (grey) tsim los ntawm txoj haujlwm ntawd, pom qhov chaw ntawm qhov cuam tshuam. Nws tuaj yeem pom los ntawm daim duab 4 tias txoj kev no tuaj yeem nrhiav qhov chaw ntawm qhov cuam tshuam sai rau ob qho tib si broadband cuam tshuam thiab kev cuam tshuam nqaim.

Ceev nrooj nrhiav qhov chaw ntawm electromagnetic cuam tshuam

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Lub spectrum analyzer yog ib qho cuab yeej rau kev kawm cov qauv spectrum ntawm cov teeb liab hluav taws xob. Nws yog siv los ntsuas cov teeb liab distortion, hloov kho, spectral purity, zaus stability, thiab intermodulation distortion. Nws tuaj yeem siv los ntsuas qee lub tshuab hluav taws xob xws li amplifiers thiab lim. Parameter yog ntau lub hom phiaj hluav taws xob ntsuas ntsuas. Nws tseem tuaj yeem hu ua zaus oscilloscope, taug qab oscilloscope, tsom xam oscilloscope, harmonic analyzer, zaus tus yam ntxwv analyzer lossis Fourier analyzer. Niaj hnub nimno spectrum analyzers tuaj yeem tso saib cov txiaj ntsig kev soj ntsuam hauv analog lossis digital txoj hauv kev, thiab tuaj yeem txheeb xyuas cov teeb liab hluav taws xob hauv txhua lub xov tooj cua zaus band los ntawm cov zaus tsawg heev mus rau sub-millimeter yoj bands hauv qab 1 Hz.

Siv lub spectrum analyzer thiab ib qho kev sojntsuam ze ze tuaj yeem nrhiav “kev cuam tshuam qhov chaw”. Ntawm no peb siv txoj kev ntawm “kev tua hluav taws” ua piv txwv. Qhov kev xeem nyob deb (EMC standard test) tuaj yeem muab piv rau “kev kuaj pom hluav taws”. Yog tias qhov taw qhia zaus tshaj tus nqi txwv, nws raug suav hais tias yog ” pom muaj hluav taws.” Cov tshuaj “spectrum analyzer + ib qho kev sojntsuam” kev daws teeb meem feem ntau yog siv los ntawm EMI engineers los kuaj xyuas “los ntawm qhov twg ntawm lub chassis cov nplaim tawm tuaj”. Tom qab pom cov nplaim hluav taws, cov txheej txheem EMI kev tua hluav taws yog siv los tiv thaiv thiab lim. “Flame” yog nyob rau hauv cov khoom. Emscan tso cai rau peb txheeb xyuas qhov chaw cuam tshuam-“hluav taws”, tab sis kuj pom “hluav taws”, uas yog, txoj kev cuam tshuam qhov chaw kis mus.

Nws tuaj yeem pom tseeb tias siv “cov ntaub ntawv xov tooj hluav taws xob ua kom tiav”, nws yooj yim heev los nrhiav cov khoom siv hluav taws xob cuam tshuam, tsis tsuas yog tuaj yeem daws qhov teeb meem ntawm qhov nqaim hluav taws xob cuam tshuam, tab sis kuj tseem siv tau rau broadband electromagnetic cuam tshuam.

Txoj kev dav yog raws li hauv qab no:

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

(1) Tshawb xyuas qhov kev faib tawm ntawm lub hauv paus nthwv dej, thiab pom lub cev qhov chaw nrog qhov loj tshaj plaws ntawm qhov loj tshaj plaws ntawm daim ntawv qhia spatial faib ntawm lub hauv paus yoj. Rau broadband cuam tshuam, qhia qhov zaus nyob rau hauv nruab nrab ntawm kev cuam tshuam broadband (piv txwv li, 60MHz-80MHz broadband cuam tshuam, peb tuaj yeem hais qhia 70MHz), tshawb xyuas qhov chaw faib tawm ntawm qhov zaus, thiab nrhiav lub cev qhov chaw nrog qhov loj tshaj plaws amplitude.

(2) Qhia qhov chaw thiab saib cov spectrogram ntawm qhov chaw. Xyuas seb qhov amplitude ntawm txhua qhov kev sib haum xeeb ntawm txoj haujlwm no coincides nrog tag nrho cov spectrogram. Yog tias lawv sib tshooj, nws txhais tau hais tias qhov chaw xaiv yog qhov chaw muaj zog tshaj plaws uas tsim cov kev cuam tshuam no. Rau broadband cuam tshuam, xyuas seb qhov chaw yog qhov chaw siab tshaj plaws ntawm tag nrho cov kev cuam tshuam broadband.

(3) Feem ntau, tsis yog txhua qhov kev sib haum xeeb raug tsim los ntawm ib qho chaw. Qee lub sij hawm txawm tias harmonics thiab khib harmonics raug tsim nyob rau ntawm qhov chaw sib txawv, los yog txhua qhov kev sib haum xeeb yuav raug tsim tawm ntawm qhov chaw sib txawv. Nyob rau hauv rooj plaub no, koj tuaj yeem nrhiav qhov chaw nrog cov hluav taws xob muaj zog tshaj plaws los ntawm kev saib ntawm qhov chaw faib tawm ntawm cov ntsiab lus zaus koj nyiam.

(4) Kev ntsuas nyob rau hauv cov chaw uas muaj hluav taws xob muaj zog tshaj plaws yog qhov kev daws teeb meem zoo tshaj plaws rau EMI / EMC.

Qhov no EMI txoj kev tshawb nrhiav uas tuaj yeem taug qab “qhov chaw” thiab kev nthuav tawm txoj hauv kev tso cai rau cov kws ua haujlwm tshem tawm cov teeb meem EMI ntawm tus nqi qis tshaj thiab ceev tshaj plaws. Hauv qhov ntsuas qhov tseeb ntawm cov cuab yeej sib txuas lus, hluav taws xob cuam tshuam los ntawm lub xov tooj kab cable. Tom qab siv EMSCAN los ua kom tiav cov lus hais saum toj no taug qab thiab tshuaj ntsuam, ob peb lub lim dej ntxiv thaum kawg tau teeb tsa rau ntawm lub rooj tsavxwm processor, uas daws qhov teeb meem EMI uas tus engineer daws tsis tau.

Ceev nrooj nrhiav qhov chaw ua txhaum ntawm Circuit Court

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Nrog rau qhov nce ntawm PCB nyuaj, qhov nyuaj thiab kev ua haujlwm ntawm kev debugging tseem nce ntxiv. Nrog lub oscilloscope lossis logic analyzer, tsuas yog ib lossis tsawg tus lej ntawm cov kab teeb liab tuaj yeem pom tib lub sijhawm. Txawm li cas los xij, tej zaum yuav muaj ntau txhiab kab teeb liab ntawm PCB. Engineers tsuas tuaj yeem pom qhov teeb meem los ntawm kev paub lossis hmoov zoo. Qhov teeb meem.

Yog tias peb muaj “cov ntaub ntawv xov tooj hluav taws xob ua tiav” ntawm lub rooj tsav xwm ib txwm muaj thiab lub rooj tsav xwm tsis zoo, peb tuaj yeem sib piv cov ntaub ntawv ntawm ob qho tib si kom pom qhov txawv txav tsis zoo, thiab tom qab ntawd siv “kev cuam tshuam qhov chaw siv tshuab” kom paub qhov chaw ntawm qhov chaw. txawv txav zaus spectrum. Nrhiav qhov chaw thiab ua rau tsis ua haujlwm.

Daim duab 5 qhia qhov zaus spectrum ntawm lub rooj tsavxwm ib txwm thiab lub rooj tsavxwm faulty. Los ntawm kev sib piv, nws yog ib qho yooj yim mus nrhiav tau hais tias muaj ib tug txawv txav broadband cuam tshuam rau lub faulty board.

Tom qab ntawd nrhiav qhov chaw nyob qhov twg qhov “hloov zaus spectrum” no yog tsim nyob rau hauv daim ntawv qhia spatial faib ntawm lub faulty board, raws li qhia nyob rau hauv daim duab 6. Nyob rau hauv no txoj kev, qhov txhaum qhov chaw nyob rau ntawm ib daim phiaj (7.6mm × 7.6mm), thiab qhov teeb meem tuaj yeem loj heev. Kev kuaj mob yuav ua sai sai.

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Cov ntaub ntawv thov rau kev ntsuas PCB tsim zoo

Ib tug zoo PCB yuav tsum tau ua tib zoo tsim los ntawm ib tug engineer. Cov teeb meem uas yuav tsum tau xav txog muaj xws li:

(1) Tsim nyog cascading tsim

Tshwj xeeb tshaj yog qhov kev npaj ntawm lub dav hlau hauv av thiab lub dav hlau fais fab, thiab kev tsim cov txheej txheem uas muaj cov kab hluav taws xob rhiab thiab cov kab teeb liab uas tsim hluav taws xob ntau nyob. Kuj tseem muaj kev faib tawm ntawm lub dav hlau hauv av thiab lub dav hlau fais fab, thiab kev sib tw ntawm cov kab teeb liab hla ntawm thaj chaw sib faib.

(2) Khaws cov teeb liab kab impedance kom tas mus li

Raws li ob peb vias li sai tau; raws li ob peb txoj kab txoj cai raws li qhov ua tau; thiab tsawg npaum li qhov ua tau tam sim no rov qab cheeb tsam, nws tuaj yeem tsim kom muaj kev sib haum xeeb tsawg dua thiab qis dua hluav taws xob siv.

(3) Lub zog lim zoo

Tsim nyog lim capacitor hom, capacitance tus nqi, kom muaj nuj nqis, thiab qhov chaw tso kawm, nrog rau cov txheej txheem tsim nyog ntawm lub dav hlau hauv av thiab lub dav hlau fais fab, tuaj yeem xyuas kom meej tias kev cuam tshuam electromagnetic raug tswj nyob rau hauv qhov chaw tsawg tshaj plaws.

(4) Sim ua kom muaj kev ncaj ncees ntawm lub dav hlau hauv av

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Raws li ob peb vias li sai tau; tsim nyog ntawm kev nyab xeeb; tsim nyog ntaus ntawv layout; tsim nyog los ntawm kev npaj kom muaj kev ncaj ncees ntawm lub dav hlau hauv av mus rau qhov loj tshaj plaws. On qhov tsis tooj, tuab vias thiab loj heev ntawm kev ruaj ntseg yov, los yog tsis tsim nyog ntaus ntawv layout, yuav tiag muaj feem xyuam rau lub sam xeeb ntawm cov av dav hlau thiab lub hwj chim dav hlau, ua rau ib tug loj npaum li cas ntawm inductive crosstalk, ntau hom tawg, thiab yuav ua rau lub Circuit Court Ntau rhiab rau kev cuam tshuam sab nraud.

(5) Nrhiav kev sib haum xeeb ntawm cov teeb liab kev ncaj ncees thiab electromagnetic compatibility

Ntawm qhov chaw ntawm kev ua kom lub cev ua haujlwm ntawm cov khoom siv, ua kom lub sijhawm nce thiab poob ntawm lub teeb liab kom ntau li ntau tau kom txo tau qhov amplitude thiab tus naj npawb ntawm harmonics ntawm electromagnetic hluav taws xob generated los ntawm lub teeb liab. Piv txwv li, koj yuav tsum xaiv qhov tsim nyog damping resistor, ib txoj kev lim dej tsim nyog, thiab lwm yam.

Yav dhau los, kev siv cov ntaub ntawv ua tiav electromagnetic teb tsim los ntawm PCB tuaj yeem tshawb xyuas qhov zoo ntawm PCB tsim. Siv cov ntaub ntawv electromagnetic tag nrho ntawm PCB, kev tsim qauv zoo ntawm PCB tuaj yeem raug soj ntsuam los ntawm plaub yam hauv qab no: 1. Tus naj npawb ntawm cov ntsiab lus zaus: tus naj npawb ntawm cov harmonics. 2. Transient cuam tshuam: tsis ruaj khov electromagnetic cuam tshuam. 3. Kev siv hluav taws xob: qhov loj ntawm electromagnetic cuam tshuam ntawm txhua qhov zaus. 4. Qhov chaw faib khoom: qhov loj ntawm qhov chaw faib hluav taws xob cuam tshuam ntawm txhua qhov zaus ntawm PCB.

Hauv qhov piv txwv hauv qab no, A pawg thawj coj saib yog kev txhim kho ntawm pawg thawj coj saib B. Daim duab schematic ntawm ob lub rooj tsavxwm thiab cov txheej txheem ntawm cov khoom tseem ceeb yog tib yam. Cov txiaj ntsig ntawm spectrum / spatial scanning ntawm ob lub rooj tsavxwm tau pom hauv daim duab 7:

Los ntawm spectrogram hauv daim duab 7, nws tuaj yeem pom tias qhov zoo ntawm A pawg thawj coj saib pom tseeb zoo dua li ntawm B pawg thawj coj saib, vim tias:

1. Tus naj npawb ntawm cov ntsiab lus zaus ntawm A pawg thawj coj saib pom tseeb tsawg dua li ntawm pawg B;

2. Lub amplitude ntawm feem ntau zaus cov ntsiab lus ntawm lub rooj tsavxwm A yog me dua li ntawm lub rooj tsavxwm B;

3. Qhov kev cuam tshuam tsis ntev los no (cov ntsiab lus zaus uas tsis cim) ntawm lub rooj tsav xwm A yog tsawg dua li ntawm pawg thawj coj B.

Yuav ua li cas kom tau txais thiab siv cov ntaub ntawv PCB electromagnetic

Nws tuaj yeem pom los ntawm daim duab kos duab qhov chaw uas tag nrho cov khoom siv hluav taws xob cuam tshuam qhov chaw faib khoom ntawm A phaj yog tsawg dua li ntawm B phaj. Cia peb saib ntawm qhov cuam tshuam ntawm electromagnetic cuam tshuam ntawm ib qho chaw zaus. Kev txiav txim siab los ntawm kev cuam tshuam ntawm electromagnetic cuam tshuam ntawm 462MHz zaus taw tes qhia hauv daim duab 8, qhov amplitude ntawm A phaj yog me me thiab thaj tsam me me. B pawg thawj coj saib muaj ntau yam loj thiab thaj chaw tshwj xeeb tshaj plaws.

Cov ntsiab lus ntawm kab lus no

Cov ntaub ntawv ua tiav electromagnetic ntawm PCB tso cai rau peb kom muaj kev nkag siab zoo ntawm tag nrho PCB, uas tsis yog tsuas yog pab cov engineers daws teeb meem EMI / EMC, tab sis kuj pab engineers debug PCB thiab txuas ntxiv txhim kho tus tsim zoo ntawm PCB. Ib yam li ntawd, muaj ntau daim ntawv thov ntawm EMSCAN, xws li pab engineers daws teeb meem electromagnetic susceptibility thiab hais txog.