Kutendeseka kwechiratidzo kwakakosha zvakanyanya mukukurumidza PCB dhizaini dhizaini. Pasina iyo, zviratidzo zvinogona kupera simba, zvichikonzera kukanganisa uye kuita kwakaipa. Matambudziko senge electromagnetic interference (EMI), impedance mismatches, uye kunonoka kunogona kuitika. Semuyenzaniso:
Miedzo inoratidza kuti kurembera maVIAs anogona kuita sediki capacitor kana antennas, zvichiita kuti EMI iwedzere.
Mateki asina kutenderedzwa negirazi fiber weave anogona kushandura impedance uye kukanganisa masaini.
Kugadzirisa matambudziko aya, unogona kuvandudza dhizaini yekutevera muPCB yako dhizaini dhizaini, tora zvirinani zvinhu, uye kudzora EMI zvakanaka.
Zvitsva Zvitsva
Simba remasaini rakakosha zvikuru kumaPCB anokurumidza. Rinochengetedza masaini akajeka uye rinodzivisa zvikanganiso kana matambudziko.
Sarudza zvinhu zvine yakaderera dielectric kugara uye kurasikirwa tangent. Izvi zvinobatsira masaini kuti arambe akasimba uye anovandudza mashandiro.
Ita kuti mitsva ipfupi uye udzivise kukona kwakapinza paunenge uchifamba. Izvi zvinoderedza kurasikirwa kwechiratidzo uye kuderedza kupindira (EMI).
Shandisa mapeya akasiyana kuchengetedza masaini uye kuderedza ruzha. Kufananidza kureba kwekutsvaga uye kuparadzaniswa kunobatsira masaini kuti agare akajeka.
Wedzera dziviriro nepasi kuti uderedze EMI. Mapurani epasi nezvifukidziro zvesimbi zvinodzivirira zvikamu uye zvinovandudza kunaka kwemasaini.
Kunzwisisa Chiratidzo Kutendeseka muYakakwira-Speed PCB Dhizaini
Chii chinonzi Signal Integrity?
Kuvimbika kwechiratidzo kunoreva kuchengetedza chiratidzo chakasimba uye chakajeka pachiri kufamba nePCB inokurumidza. Pakumhanya kusvika ku4 GHz, kubatana kunoshanda semitsetse yekutumira. Izvi zvinogona kukonzera matambudziko akadai seruzha, kunonoka, uye shanduko dzechiratidzo. Kuvimbika kwechiratidzo kwakakosha kuchengetedza zviratidzo zvakachena uye nenguva kuti zvishande zvakanaka.
Kuti uchengetedze masaini akasimba, unofanirwa kugadzirisa nyaya senge maratidziro, crosstalk, uye EMI. Kuedza uye kuenzanisa kunobatsira kuwana nekugadzirisa matambudziko aya. Zviyero zvakaita seIEEE 802.3ap inoisa mitemo yekuita chokwadi chepamusoro-kumhanya maPCB anoshanda nenzira imwechete.
Kuonekwa | Zvazvinoreva |
|---|---|
Sei Kutevedzera Kunokosha | Vanobatsira kugadzira mitemo yezvibatanidza zvinokurumidza. |
Signal Kuperera Matambudziko | Nyaya dzinosanganisira kuratidzira, crosstalk, uye kushaya simba kwechiratidzo. |
Kuita Mitemo | Mapoka akaita sePIMGG uye OBSAI anogadzira zviratidzo zvekuvimbika. |
IEEE Mitemo | Isa miganhu yekuti machanera anofanira kuita sei. |
Matambudziko muHigh-Speed PCB Layouts
Fast PCB masisitimu ane akawanda matambudziko anokuvadza chiratidzo chemhando:
Crosstalk inoitika kana masiginecha ari munzira dziri pedyo akanganisa.
Kusawirirana kweImpedance kunoita kuti zviratidzo zvidzokere shure, zvichiita kuti zvikanganiso zviitike.
Kushata nzira pamusoro pendege dzakapatsanuka kunoita ruzha uye EMI iwedzere.
Soldering zvikanganiso, senge mapundu mukubatanidza, anonetesa masaini.
Aya matambudziko anogona kuita kuti PCB yako ishande zvisina kunaka. Semuyenzaniso, kutsemuka mu vias diki kana shanduko yezvinhu zvinogona kukanganisa masaini. Kuti ugadzirise izvi, shandisa nzira dzakaita sechiratidzo chekusiyanisa, kumisa kwakaringana, uye kucherechedzwa kwevarindi.
Zvakaipa Sei Chiratidzo Kuvimbika Kunokanganisa Kuita
Kutendeseka kwakashata kwechiratidzo kunogona kuita kuti PCB yako ishande zvakashata. Zviratidzo zvinogona kurasikirwa nechimiro chazvo, zvichiita kuti zvishandiso zviverenge zvisizvo. Impedance mismatches uye yakakwirira-frequency inoderedza simba rechiratidzo chepasi, zvichikonzera kumhanya kunononoka uye kukanganisa.
Ruzha rwekuwedzera, senge jitter kana shanduko yemagetsi, inoshatisa nguva yechiratidzo. Ground bounce inogona kuchinja voltage level, zvichikonzera kukanganisa. Crosstalk inowedzera zviratidzo zvisingadiwe kunzira dziri pedyo, zvichiita kuti data isanyanya kurongeka.
Kuti umise matambudziko aya, shandisa yakatsiga yereferensi ndege yekukurumidza masaini. Izvi zvinoderedza ruzha uye EMI, kuchengetedza masaini akajeka. Kugadzirisa nyaya idzi kunoita kuti PCB yako ive yakavimbika uye iite zvirinani.
Mazano Akakosha ePamusoro-Kumhanya PCB Magadzirirwo Dhizaini
Kusarudzwa kwezvinhu zveChiratidzo cheKutendeseka
Kusarudza zvinhu zvakakodzera ndiko kwakakosha pakuchengetedza zviratidzo zvakasimba. Zvinhu zvaunoshandisa zvinokanganisa kufamba kwezviratidzo muPCB. Zvinhu zvine dielectric constant shoma ( Dk ) uye loss tangent ( Df ) zvinobatsira zviratidzo kuti zvirambe zvakajeka uye zvakasimba.
pfuma | Nyaya |
|---|---|
Dielectric Constant ( Dk ) | Sarudza zvinhu zvine Df yakaderera (<0.005) yekushandisa RF uye microwave. |
Kuwanda kweThermal Coefficient ( CTE ) | Shandisa ma laminate ane CTE yakaderera (10 kusvika 20 ppm/°C) kuti ugare wakasimba. |
Substrate Ukobvu | Sarudza ma substrates akatetepa (10 kusvika 20 mil) kuti awane ma frequency akakwira kupfuura 10 GHz. |
Kurasikirwa Tangent | Sarudza zvinhu zvine yakaderera kurasikirwa tangents (0.0022 kusvika 0.0095) kuderedza chiratidzo kurasikirwa. |
Kunyorova Kusviba | Sarudza zvinhu zvine hunyoro hwemvura yakaderera (<0.1%) kuti uite zvirinani. |
Tarisa ruzivo rwezvinhu nokungwarira. Miedzo inoratidza kuti kukosha kweDf chaiyo kunogona kusiyana nezvakanyorwa nevatengesi. Kunyangwe musiyano mudiki, senge 0.004 muDf , unogona kuwedzera kurasikirwa kwechiratidzo. Kuedza zvinhu usati wagadzira PCB yako kunobatsira kudzivirira matambudziko aya.
Trace Dhizaini uye Routing Maitiro Akanakisa
Yakanaka trace dhizaini uye nzira yakakosha kune inokurumidza PCBs. Mapfupi anoteedzera anochengeta masaini akasimba uye anoderedza zvisingadiwe mhedzisiro. Inodzorwa impedance inoita kuti shuwa maronda aenderane nezvikamu zvakabatana, zvichichengeta masaini akajeka.
Maitiro Akanyanya | Tsanangudzo |
|---|---|
Chengeta mitsva ipfupi | Tsanangudzo pfupi dzinodzikisa mukana wekurasikirwa kwechiratidzo uye zvisingadiwe mhedzisiro. |
Shandisa controlled impedance | Machesi anoteedzera impedance kuderedza zviratidzo zvechiratidzo uye kuchengetedza masaini akajeka. |
Nzira nokungwarira | Dzivisa makona akapinza uye kumisa vias kudzikisa kurasikirwa kwechiratidzo uye crosstalk. |
Dzivisa makona akapinza paunenge uchironga marongero enzira. Makona akapinza anogona kukonzera kuratidzwa kwezviratidzo uye EMI yakawanda . Shandisa ma curves akatsetseka kana ma angle e 45-degree panzvimbo pezvo. Deredza ma vias nekuti anowedzera mhedzisiro isingadiwe iyo inoshayisa simba ma signals. Zvishandiso zvakaita seAltium Designer neCadence zvinogona kukubatsira kuvandudza PCB routing yako.
Kushandisa iyo 20-H Rule Kuderedza EMI
Mutemo we20-H unobatsira kudzikisa EMI mumarongero ePCB anokurumidza. Zvinoreva kudzikisa denga remagetsi neka20 kukwirira kwedenga riri pakati pesimba nendege dzepasi. Izvi zvinoderedza kuburitswa kweRF pamafrequencies akaderera.
Yokudzidza | Zviwanikwa |
|---|---|
Clemson University Kudzidza | Kutevera mutemo we20-H cheka kuburitswa kweRF pasi pe300 MHz ne ~ 5 dBμV/m. |
Yunivhesiti Test Boards | Miedzo yakaratidza kuti mutemo we20-H wakonzera EMI yakaipa kupfuura flush power ne ground planes. |
Mutemo we20-H unoshanda zvirinani pamafrequencies akaderera. Pafrequencies dzakakwirira, zvinogona kuita kuti EMI iwedzere kuipa. Kune maPCB anokurumidza, tarisa kana mutemo we20-H uchienderana nezvaunoda. Dzimwe nguva, kuchengetedza simba nepasi pevhu zvichishanda zvirinani.
Zano: Edza dhizaini yako yePCB mumamiriro ezvinhu chaiwo kuti uwane nzira yakanakisa yekuderedza EMI.
Component-Level Dhizaini Kufunga
Kugadzirisa Kusefa Capacitance
Kusefa capacitor kwakakosha pakuchengetedza masaini akajeka muPCB dzinokurumidza. Sarudza ma capacitor anoenderana nema frequency anodiwa padhizaini yako. Vanobatsira kubvisa ruzha uye kuchengetedza voltage kuti iite zvirinani.
Kuvandudza kusefa, tarisa kuti unoshandisa kupi uye sei ma capacitors. Zviise pedyo nemapini emagetsi kuderedza zvisingadiwe. Shandisa ese madiki uye makuru capacitor kubata akasiyana ma frequency. Semuyenzaniso, kushandisa 0.1 µF uye 10 µF capacitor pamwe chete kunogona kuvharidzira ruzha-ruzha uye yakatsiga yakadzika ma frequency.
Madhizaini anokurumidza anowanzo shandisa mainterface senge USB, DDR, PCIe, uye Ethernet. Izvi zvinoda chaiyo impedance control kutumira data nemazvo. Bata zvikamu zvekugumisa zvakanyatsonaka uye isa mitemo yezvikwangwani zvekumhanya. Kufambisa neinodzorwa impedance inochengeta masaini akajeka uye akasimba.
Iyo Signal Integrity chishandiso inowana mambure ane zvinobvira matambudziko ekufungidzira. Iyo inoyera waveforms zvakananga, ichikubatsira iwe kuvandudza dhizaini yako kune zvirinani mhedzisiro.
Iko hakuna mitemo yakagadziriswa yekukurumidza PCB dhizaini, asi maitiro akanaka anobatsira zvakanyanya. Maturusi ekuyedza uye ekufananidza anogona kutarisa yako capacitor sarudzo uye kugadzirisa kujeka kwechiratidzo.
Basa reSilicon Packaging muYakakwira-Speed PCB Dhizaini
Silicon kurongedza inokanganisa chiratidzo chemhando mukukurumidza PCB dhizaini. Iyo pasuru yemagetsi network inoita senge musanganiswa wemacapacitor uye inductors. Izvi zvinoshandura mabatiro azvinoita kukurumidza magetsi pulses, zvichikanganisa kuita kwePCB.
On-chip simba impedance ndiyo kiyi yesimba uye chiratidzo chemhando. Inobatanidza zvakanyanya kune kujekesa kwechiratidzo, kunyanya pamafafitera epamusoro. Sezvo machipisi anoshanda paGHz kumhanya, iyo simba network's impedance inoshanduka. Izvi zvinoshandura kunaka kwechiratidzo uye kuita kwese.
Tsanangudzo Yeuchapupu | Kukanganisa paChiratidzo Kutendeseka |
|---|---|
Package simba network inoita senge capacitors uye inductors | Inochinja mabatirwo anoitwa mapurusi, zvichikanganisa kuita kwePCB |
On-chip simba impedance inokanganisa kunaka kwesimba | Yakanyatsobatanidzwa nekujekesa kwechiratidzo mumagadzirirwo epamusoro-frequency |
Impedance inoshanduka neGHz-kumhanya maseketi | Inoshandura kunaka kwechiratidzo uye zvinokanganisa kuita |
Kuti uvandudze kurongedza kwesilicon, dzidza maitiro ayo emagetsi uye kuti anoshanda sei nePCB. Shandisa maturusi ekufananidza kutarisa impedance uye kuwana matambudziko. Kugadzirisa nyaya idzi kunonatsiridza mhando yechiratidzo uye kunoita kuti PCB yako ishande zvirinani mumagadzirirwo anokurumidza.
Kugadzirisa EMI uye Common-Mode Currents
Kunzwisisa Differential-Mode vs. Common-Mode Currents
Mumagadzirirwo ePCB anokurumidza, ma "differential-mode" ne "common-mode currents" anoshanda zvakasiyana. Ma "differential-mode currents" anotakura data pakati penzira dzechiratidzo nedzokudzoka. Ma "common-mode currents" anoitika nekuda kwekusawirirana kwedunhu uye kuyerera kwenzira dzisingadiwe. Izvi zvinowanzo kukonzera EMI.
Nzira dzisina kuenzana dzemasaini dzinogona kuwedzera ruzha rwe common-mode uye EMI . Semuenzaniso:
Kusaenzana nzvimbo pakati pepasi uye chiratidzo vias zvinokonzeresa kutendeuka kwemodhi.
Zvisina kufananidzwa zvakasiyana pairi zvinogona kugadzira kusvika -40 dB yeruzha.
Tsvagiridzo inoratidza kuti kuchengetedza symmetry muzviratidzo kunoderedza EMI ne80 dB.
Mapairi akasiyana anobatsira kuderedza EMI uye kudzivirira ruzha. Anoenzanisa masaini, izvo zvakakosha pakugadzira nekukurumidza. Anotarisa pane marongero akafanana uye nzira dzakanaka dzekudzoka kudzora ma common-mode currents.
Matekiniki ekudzikisa Yakajairwa-Modhi Yazvino Radiation
Kudzikisa zvakajairika-modhi ikozvino mwaranzi inochengeta masaini akasimba mukukurumidza PCBs. Edza nzira idzi:
Vandudza Differential Pair Routing : Enzanisa hurefu hwetrace uye chengeta nzvimbo yakaenzana.
Isa Ground Vias Well : Isa ground vias pedyo nesignal vias kuti ugone kuchinja stop mode.
Shandisa Kugumisa Kwakakodzera : Match impedance kumagumo kudzivirira kuratidzwa.
Miedzo inoratidza kuti kupatsanura ma common-mode currents kwakakosha. Vachishandisa ma probe, vaongorori vakayera ma currents aya nekuisa waya mukati me probe. Izvi zvakabatsira kudzidza EMI uye kufananidza ma FDTD modes.
Measurement Technique | Zvazvinoita | Results |
|---|---|---|
Common-modhi ikozvino kuyerwa | Inoshandisa probe kuyera pedyo-munda mafungu. | Mhedzisiro yeEMI yakaenzana nemamodheru eFDTD. |
Differential-modhi ikozvino kuyerwa | Inoyera huwandu hwemagetsi mumaseti akasiyana. | Mhedzisiro inoratidzwa mune hukama dBµV kukosha. |
FCC inodzika mitemo yakajairika-modhi ikozvino yeClass A uye B zvigadzirwa. Pa30 MHz, Zvigadzirwa zveKirasi A zvinofanirwa kugara pasi pe24 µA, uye Kirasi B pasi pe8 µA.
Kutevera iyi mitemo uye nekuvandudza PCB yako dhizaini inogona kucheka yakajairika-modhi radiation uye kuwedzera mashandiro.
Kudzivirira uye Kudzika Matanho eEMI Kuderedza
Kudzivirira nekusimbisa ivhu inzira dzakanaka dzekuderedza EMI mumaPCB anomhanya. Kudzivirira kunoita kuti magetsi asingadiwe arambe akasimba. Kudzivirira kunodzivirira minda yemagetsi kuti isapinde kana kubuda muPCB.
Kudzivirira zvinobudirira:
Shandisa zvivharo zvesimbi kana maconductive coatings pazvikamu zvakaomarara.
Wedzera mapuraneti epasi pasi pemitsara yezviratidzo zvinokurumidza kuti utore EMI.
Ita shuwa kuti kubatanidza kwepasi kunoramba kuchienderera mberi kudzivirira mapundu anoita sema antenna.
Kugadzika zvakanaka kunoita kuti pave nenzira dzakasimba dzekudzoka kwemagetsi emhando dzakasiyana. Kusaenzana kwepasi kunogona kukonzera kushandurwa kwemuchina uye kuwedzera EMI . Zvidzidzo zvinoratidza kuti marongero akafanana anogona kuderedza EMI ne60 dB.
Kune maPCB anokurumidza, sanganisai kudzivirira nekusimbisa pasi kuti muderedze EMI . Nzira idzi dzinovandudza kunaka kwemasaini uye dzinosangana nemitemo.
Mazano epamberi ePamusoro-Speed PCB Layout Dhizaini
Kushandisa Reference Planes uye Controlled Impedance Traces
Kuti zviratidzo zvirambe zvakajeka mumagadzirirwo anokurumidza, shandisa mapurani ekutarisa. Zviratidzo zve impedance zvinodzorwa zvakakoshawo. Kana impedance ikachinja, zviratidzo zvinogona kudzoka. Izvi zvinoderedza data uye zvinokonzera zvikanganiso. Mapurani epasi nemagetsi anobatsira zviratidzo kudzoka zvakanaka uye kudzikisa EMI.
Paunenge uchironga nzira, chengeta marongero mapfupi uye dzivisa maangle akapinza. Kutenderera kwakapinza kunogona kukanganisa masaini uye kuwedzera EMI . Shandisa ma curves akatsetseka kana ma angle e 45-degree panzvimbo pezvo. Kuronga nzira kwakanaka uye ma planes akasimba anoita kuti masaini ave akachena uye anovandudza mashandiro.
Zano: Shandisa maturusi ekufananidzira kuti utarise impedance uye uwane matambudziko.
Kuderedza Vias uye Kupfupisa Trace Lengths
Shorter traces uye mashoma vias zviri nani kumhanyisa PCBs. Mapfupi anoteedzera kunonoka kwechiratidzo kunonoka uye kumisa impedance mismatches. Chengetedza kureba pasi pe2 inches kuti uwane mibairo yakanaka. Izvi zvinochengeta zviratidzo zvakasimba uye zvakavimbika.
Tsanangudzo Yeuchapupu | Kiyi Insight |
|---|---|
Mapfupi maronda ari nani. | Vanodzikisa kunonoka kwechiratidzo uye kusawirirana kwe impedance. |
Maronda ari pasi pe 2 inches anoshanda zvakanyanya. | Tsanangudzo pfupi dzinoderedza kunonoka uye kusawirirana matambudziko. |
Isa vias pedyo pamwe chete. | Grouped vias inovandudza conductivity uye yakaderera resistive kurasikirwa. |
Isa vias padhuze kune imwe neimwe kuti uvandudze kuyerera kwechiratidzo. Izvi zvinoderedza kuramba uye zvinowedzera kushanda. Usashandise vias akawanda, sezvo anogona kukonzera zvisingadiwi mhedzisiro.
Kumhanya Yepamusoro-Frequency Signals paInner Layers
Isa masaini epamusoro-soro pazvikamu zvemukati kuti zvive nani. Matunhu emukati anoita kuti nzira dzechiratidzo dziite pfupi. Izvi zvinodzikisira kunonoka uye zvinomisa chiratidzo kubhanhira. Diki vias zvakare kuderedza matambudziko akaita stubs uye mismatched impedance.
Mapurani emagetsi nepasi pazvikamu zvemukati zvinobatsira zvakanyanya. Anoderedza ruzha uye kutaura, zvichipa zviratidzo nzira yakatsetseka. Mapurani aya anovharawo EMI nekuderedza kusvetuka kwepasi uye ruzha rwesimba.
Cherechedza: Kugadzika kwePCB layer kunokanganisa impedance. Zvinhu zvakaita sehupamhi hwetrace, rudzi rwezvinhu, uye daro kubva kumapuraneti zvakakosha zvikuru.
Gadzira yako PCB maseru nemazvo. Izvi zvinovandudza simba rechiratidzo uye zvinoita kuti zvigadziriso zvinokurumidza zvishande zvirinani.
Kuita masaini zvirinani mukukurumidza PCB marongero, ronga nemazvo. Unogona kuvandudza nekufambisa zviteshi zvakanaka, uchishandisa zvinhu zvakanaka, uye kudzora EMI. Semuenzaniso, 5G network inoshanda zvirinani ine yakasimba EMI nhoo uye yakanaka trace dhizaini. Saizvozvo, zvishandiso zvinogara zvakashongedzwa uye kuderedza EMI nekusefa masaini uye nekuafambisa zvine hungwaru.
Urongwa hwakakwana hunobatsira basa rako redunhu zvakanaka mumamiriro ese ezvinhu. Nekutora zvinhu zvakanaka, kutenderera chaiko, uye nekuwedzera nhovo dzakanaka, dunhu rako rinogona kuzadzisa zvinangwa zvaro. Shandisa matipi aya kuita kuti dhizaini yako ive nani uye uwane mibairo mikuru nguva dzese.
FAQ
Chii chinonyanya kukosha pakutendeseka kwechiratidzo mukukurumidza PCB marongero?
Kusarudza zvinhu zvakakodzera kwakakosha zvikuru. Sarudza zvinhu zvine dielectric constant shoma ( Dk ) uye loss tangent ( Df ) kuti zviratidzo zvirambe zvakajeka. Izvi zvinobatsira kuderedza kurasikirwa kwezviratidzo uye kuvandudza mashandiro emagadzirirwo ekumhanya kukuru.
Iwe unogona sei kudzikisa EMI mukukurumidza PCB magadzirirwo?
Iwe unogona kudzikisa EMI nekushandisa nhovo, pasi, uye nzira dzakanaka dzekutevera. Isa ndege dzepasi pasi pemitsara yezviratidzo uye dzivisa kutenderera kwakapinza. Mutemo we20-H wendege dzemagetsi unobatsira kuderedza EMI panguva yakaderera.
Nei zviri nani kushandisa mashoma vias mukukurumidza PCB marongero?
Vias inogona kukonzera kunonoka kwechiratidzo uye kusawirirana. Kushandisa vias shoma kunoita kuti masaini arambe achiyerera zvakanaka uye anodzivirira matambudziko akaita semafekisheni. Kubatanidza vias pedyo pamwe chete kunonatsiridza kuyerera kwechiratidzo uye kunoderedza kuramba.
Mapaya akasiyana anobatsira sei nekuvimbika kwechiratidzo?
Vaviri vakasiyana vanochengeta zvikwangwani zvakaenzana, kucheka ruzha uye EMI. Vanotakura mafungu akapesana anodzima kupindira. Kufananidza kureba kwekutsvaga uye kuparadzanisa kunoita kuti zvishande zvirinani.
Maturusi ekuenzanisa anogona kuita kuti chiratidzo kutendeka kuve nani?
Ehe, maturusi ekufananidza anowana matambudziko akaita senge isingaenzaniswi impedance uye kuratidzwa. Vanokutendera kuti uedze magadzirirwo usati waagadzira, kuvandudza mashandiro uye kuvimbika mumaPCB anokurumidza.
Zano: Edza maturusi akaita seAltium Designer kana Cadence kuti uwane masimulation ari nani.
