Kudzikiswa kweChiratidzo muHigh-Speed ​​PCBs: Zvinokonzera, Kuongorora, uye Maitiro Ekuderedza

1. Nhanganyaya: Tsanangudzo uye Kukosha kweKuderedza Chiratidzo

Kudzikira kwechiratidzo kunoreva kudzikira zvishoma nezvishoma kwesimba rechiratidzo sezvo simba remagetsi richipararira kuburikidza netambo yekutumira yePCB. Mumasekete edhijitari neRF anomhanya zvakanyanya, chiitiko ichi chinoratidzwa nekudzikira kweamplitude yemagetsi, nguva yekukwira yakaderera, uye kudzikira kweratio yechiratidzo-kune-ruzha pamugumo wekugamuchira.

1.1 Nei Kudzikiswa Kwechiratidzo Kuchikosha Pakuvimbika Kwechiratidzo

Kudzikira kwemasaini zvakanyanya kunokanganisa kusimba kwemasaini nekukonzera kukanganiswa kwechimiro chemafungu, kuvharwa kwedhayagiramu yemaziso, uye mwero wekutadza kwemabhiti wakakwira. Sezvo mwero wedata uchiwedzera kusvika pahuwandu hwemagigabit akawanda, kunyangwe kudzikira kuri pakati nepakati kunogona kuita kuti chiteshi chisashande, zvichiita kuti kugadzirisa kurasikirwa kuve dambudziko guru rekugadzira.

1.2 Maonero eChinyorwa Chino

Chinyorwa chino chinoongorora zvinhu zvinokonzera kudzikira kwemasaini mumagadzirirwo ePCB anomhanya zvikuru uye chinopa nzira dzinoshanda dzekuderedza kurasikirwa kwekutumira. Chinangwa chinoramba chiri pakufunga nezvePCB, kubva pakusarudza zvinhu kusvika pakugadzirisa marongerwo kusvika pakugadzirisa nzira dzekubhadhara.

2. Fizikisi Yepasi Yekuderedzwa Kwechiratidzo

2.1 Muenzaniso weMutsetse weKutumira uye Kuratidzwa kweKudzikira

Matambiro ePCB anoshanda pamafrequencies akakwirira anoita semitsetse yekutumira yakagoverwa pane kuita semaconductor akareruka. Kudzikira kwechiratidzo mumitsetse iyi kunoyerwa mumadecibels pahurefu hweyuniti (dB/inch kana dB/mm), zvichimiririra chiyero chelogarithmic chesimba rinopinda kune rinobuda. Kudzikira kwese kunosanganisira zvikamu zviviri zvikuru: kurasikirwa kweconductor uye kurasikirwa kwe dielectric, chimwe nechimwe chine frequency dependencies dzakasiyana.

2.2 Kurasikirwa kweConductor muHigh-Speed ​​​​PCBs

Kuramba uye Mhedzisiro Yeganda

PaDC nepamafrequency akaderera, kurasikirwa kwemuchina wemagetsi kunonyanya kuenderana nekusasimba kwemhangura yakawanda. Zvisinei, sezvo frequency ichiwedzera, mhedzisiro yeganda inoganhurira kuyerera kwemagetsi kusvika padanho rakatetepa riri pedyo nepamusoro pemuchina wemagetsi. Kudzikiswa uku kunobudirira kwenzvimbo inoyambuka mativi kunowedzera kusimba kwemuchina wemagetsi, zvichiita kuti kurasikirwa kwemuchina wemagetsi kukure nepakati pemudzi wefrequency.

Mhedzisiro yeKuoma Kwepamusoro

Kuomarara kwepombi yemhangura kunowedzera kurasikirwa neconductor pahuwandu hwepamusoro. Kana kudzika kweganda kwasvika padanho rekuomarara, magetsi anofanira kufamba nenzira yakareba inobudirira pamwe chete nepamusoro pasina kuenzana. Kurapa kwemhangura kwakapfava senge VLP (Very Low Profile) kana HVLP foils kunoderedza kurasikirwa uku zvakanyanya.

2.3 Nzira dzeKurasikirwa neDielectric

Kurasikirwa neTangent uye Kunwa Simba

Kurasikirwa kweDielectric kunobva mukupindura kwepolarization kwezvinhu zvePCB substrate kuenda kuminda yemagetsi inochinjana. Kurasikirwa kwetangent (Df kana tan δ) kunoyera kupararira kwesimba uku, nehukuru hwepamusoro hunoratidza kunyudzwa kukuru kwechiratidzo. Kusiyana nekurasikirwa kweconductor, kurasikirwa kwedielectric kunowedzera zvakanangana nefrequency, zvichiita kuti ive dominant attenuation mechanism pa multi-gigahertz rates.

Maitiro eDielectric Akawanda-Kazhinji

Pama frequency akakwira, kurasikirwa kwe dielectric kunowanzo pfuura kurasikirwa kwe conductor senzvimbo huru yekudzikamisa magetsi. Zvinhu zve substrate zvinoratidza hunhu hwe dielectric hunoenderana ne frequency, uye kufanotaura kurasikirwa kwakarurama kunoda kutsanangura Dk naDf mu operating bandwidth pane kuvimba ne single-frequency datasheet values.

3. Zvikonzero Zvikuru zveKudzikira kweChiratidzo muKugadzira PCB Yekumhanya Kwakakwirira

3.1 Kureba kweMafambiro uye Nzira yeChiratidzo

Kudzikira kwechiratidzo kunowedzera kana mafrequency ekushanda uye matrace length. Zvikamu zvefrequency yakakwira mukati me signal spectrum zvinorasikirwa zvakanyanya, zvichikonzera frequency-dependent amplitude roll-off. Nzira dzenzira refu dzinounganidza kurasikirwa uku, zvichiita kuti kuderedza urefu hwenzira kuve chinangwa chikuru chekugadzira nzira dzinomhanya zvakanyanya.

3.2 Substrate Material Kushanda Kwayo

Chinhu chinoramba chichishandiswa mu dielectric (Dk) uye dissipation factor (Df) yezvinhu zvePCB substrate zvinokanganisa zvakanyanya kuderedzwa kwechiratidzo. Standard FR-4 inoratidza tangent values ​​yakakwira (0.020–0.025), nepo ma laminates epamusoro-soro asina kurasikirwa akadai seMegtron, specialty low-loss laminate, kana zvinhu zveIsola zvichipa Df values ​​pasi pe0.005. Kusarudzwa kwezvinhu kunosarudza zvakananga hurefu hwechiteshi chinogoneka padanho redata rakapihwa.

3.3 Kufunga Nezve Trace Geometry uye Marongerwo Ezvinhu

Upamhi hwetrace, ukobvu, uye urefu zvese zvinokanganisa kukura kwekuderera kwesimba. Trace dzakatetepa dzinoratidza kuramba kwakanyanya uye kurasikirwa kukuru kweconductor. Makona akapinza uye makotama asina kufanira anounza kusagadzikana kweimpedance uye kuwanda kwenzvimbo. Optimized trace geometry inoenzanisa zvinodiwa zvekutonga impedance zvinopesana nezvinangwa zvekuderedza kurasikirwa.

3.4 Hunhu hweCrosstalk neReturn Path

Kutaurirana pakati pemakwara ari pedyo uye kusaenderera mberi mumatanho ekutarisa kunoderedza amplitude inoshanda yechiratidzo pamareceivers. Kusafamba zvakanaka kwenzira yekudzoka kunowedzera kutenderera kweropa uye kunoita kuti pave nekubatana kwe common-impedance. Izvi zvinokonzera kurasikirwa kwakananga, zvichideredza mikana yechiratidzo.

3.5 Kuburikidza nekuchinja kwezvikamu uye shanduko dzezvikamu

MaVias anounza parasitic inductance uye capacitance izvo zvinoita kuti pave nelocalized impedance mismatches. Kuchinja kwega kwega kwe layer kunowedzera kurasikirwa kwe insertion kubva mukusiyana uku. Magadzirirwo ekumhanya kwakanyanya anoda kungwarira kuburikidza ne optimization, kusanganisira back-drilling, via-in-pad techniques , kana kuvharwa nemaziso/kuvigwa kuburikidza ne structures kuderedza kurasikirwa kwe transition.

4. Kuongorora uye Kuyera Kudzikiswa kweChiratidzo

4.1 Kuyerwa kweVector Network Analyzer Frequency-Domain

Vector network analyzers (VNAs) vanopa nzira yakajairika yekutarisa PCB channel attenuation. Kuyerwa kweS-parameter, kunyanya S21 (insertion loss), kuyera frequency-dependent transmission loss mu operating bandwidth. Matekiniki eVNA anogonesa kupatsanurwa kwakarurama kwekurasika pakati pe conductor ne dielectric mechanisms.

4.2 Zvishandiso zveSimulation zveKuongorora Dhizaini-Danho

Zvigadziriso zvemagetsi zvemagetsi uye zvinofambisa tambo zvinofanotaura kuderera kwesimba risati ragadzirwa. Zvishandiso izvi zvinotevedzera kurasikirwa kunoenderana nefrequency, zvinogadzira madhayagiramu emaziso, uye zvinoongorora mashandiro echiteshi zvichienzaniswa nemamasiki ekutevera. Kufungidzira kwekutanga kwehurongwa kunotungamira kusarudzwa kwezvinhu uye sarudzo dzekugadzirisa geometry.

4.3 Kururama kweKuenzanisa uye Kuenderana kweKuyera

Kururama kwekufananidzira kunoenderana nekutsanangurwa kwakarurama kwezvinhu uye kuvimbika kwemuenzaniso wejometri. Kusiyana pakati pemhedzisiro yakaedzwa neyakayerwa kunowanzo kukonzerwa nekushivirira kwekugadzira, mamodheru asina kukwana, kana kusiyana kwehunhu hwezvinhu zvinoenderana nefrequency. Zvidzidzo zvekubatana pakati pekuenzanisa nemakuponi ekuyedza zvinosimbisa chivimbo mumamodheru ekufanotaura.

5. Mazano Ekugadzira Kuderedza Kuderera Kwezviratidzo

5.1 Sarudzo yePCB Yezvinhu zveKurasikirwa Kwakaderera

Kusarudza zvinhu zve substrate zvine mazinga akaderera eDk neDf kunoderedza kurasikirwa kwe dielectric zvakananga. Ma laminates anorasikirwa zvishoma anova akakosha kana hurefu hwe channel huchipfuura bhajeti rekurasikirwa nezvinhu zvakajairwa. Kuchinjana kwemitengo kunotungamira kusarudzwa kwezvinhu, nekusanganiswa kwema hybrid stackups achishandisa zvinhu zvepamusoro chete kune zvikamu zvakakosha zvesignal zvinopa kubvumirana kunoshanda.

5.2 Kudzorwa kweImpedance uye Dhizaini yeStackup

Kuchengetedza kudzorwa kweimpedance munzira yese yechiratidzo kunoderedza kuratidzwa kwezviratidzo izvo zvinosanganisa kuderedzwa kwesimba remagetsi. Dhizaini yestackup inoisa ma layers echiratidzo anomhanya zvakanyanya pedyo nematanho ereferensi anoenderera mberi, zvichiita kuti nzira dzekudzoka dzisina inductance dzakaderera. Ukobvu hwe dielectric hwakafanana uye kudzora kudzorwa kweimpedance zvinoderedza kurasikirwa kunokonzerwa nekusagadzikana.

5.3 Trace Geometry uye Kugadzirisa Nzira

Makwara akafara anoderedza kurasikirwa kwemutyairi kana paine zvipingamupinyi zve impedance. Kuderedza kureba kwekwara kuburikidza ne direct routing uye kuderedza layer transitions kunoderedza cumulative attenuation. Kudzivisa acute-angle bends uye kuchengetedza mafambiro akatsetseka kunochengetedza signal amplitude.

5.4 Maitiro ekugadzirisa kuderedzwa kwemitengo

Kusimbisa ma transmitters kunowedzera zvikamu zvemasaini ane ma frequency akawanda kuti zvidzivise kurasikirwa kwechiteshi kunoenderana nema frequency. Kuenzanisa pama receiver kunoshandisa mhinduro ye inverse channel kuti idzorere huwandu hwe frequency hwakaderera. Matekiniki aya anowedzera kusvika kwechiteshi kupfuura miganhu yekurasikirwa kusingashande.

5.5 Kuenzanisa Kugumisa uye Kudzora Ruzha

Kuenzanisa kwakakodzera kwekumisa magetsi pamagumo emutyairi neanogamuchira magetsi kunobvisa kuratidzwa kwechiedza kunoderedza amplitude yechiratidzo. Nzira dzekumisa dzakatevedzana, dzakafanana, uye dzeAC dzinogadzirisa zvinodiwa zvakasiyana zvekuenzanisa impedance. Nzira dzakachena dzekugovera magetsi nekudzivirira magetsi dzinodzivirira kubatana kweruzha izvo zvinoderedza miganho inoshanda yechiratidzo.

6. Zvaunofanira Kufunga Nezvemagadzirirwo Akajairika Anomhanya Nekukurumidza

Ma "serial interfaces" anomhanyisa zvakanyanya akadai sePCIe Gen4/5, USB4, uye 100G+ Ethernet anoshanda pama "frequency" apo "signal attenuation" inonyanya kudzora zvirambidzo zvekugadzira. Aya ma "protocols" anotsanangura bhajeti repamusoro rekurasikirwa kwe "channel insertion" iro rinosarudza zvakananga hurefu hwe "trace" hunogamuchirwa uye zvinodiwa nezvinhu. RF uye mmWave applications zvinoisa zvirambidzo zvakanyanya zvekurasikirwa.

Pama frequency akawanda-gigahertz, sarudzo dzezvinhu uye geometry dzinoda kunyatsoongorora mafambiro ekuchinjana kwemari. Mapoka ekugadzira anofanira kuyera mutengo nekushanda, achisarudza giredhi repasi rezvinhu rinogutsa bhajeti rekurasikirwa kwechiteshi uku achishandisa nzira dzekubhadhara kuti zvikwanisike kusvika pazvinogoneka.

7. Mhedziso

Kudzikiswa kwechiratidzo mumaPCB anomhanyisa kunokonzerwa nemigumisiro yakabatana yekusagona kufambisa tambo, mhedzisiro yeganda, kuomarara kwenzvimbo, uye kunyudzwa kwe dielectric. Kuwanda kwezviratidzo, kureba kwenzira, hunhu hwezvinhu, hunyanzvi hwe trace geometry, uye mhando yekuchinja zvese zvinobatsira mukurasikirwa kwese kwenzira.

Kugadzirisa kuderedzwa kwesimba kunoda nzira dzakasiyana-siyana dzinosanganisira kusarudzwa kwezvinhu, dhizaini yekuisa zvinhu zvinodzorwa ne impedance, nzira dzakagadziriswa, uye matekiniki ekugadzirisa zvinhu nemagetsi. Kuenzanisa kwakarurama uye kuyera kunoita kuti magadzirirwo akwane bhajeti rekurasikirwa risati ragadzirwa.

Magadzirirwo emangwana anomhanya zvikuru achada kufambira mberi muzvinhu zvisingarasikirwe zvakanyanya, kurapwa kwemhangura kwakapfava, uye maalgorithms ekugadzirisa zvinhu akaomarara sezvo huwandu hwedata huchikwira zvakanyanya muhurongwa hwe multi-tens-of-gigahertz.