High-speed SAS Cables: Connectors uye Signal Optimization

High-speed SAS Cables: Connectors uye Signal Optimization

Signal Kutendeseka Zvinotsanangurwa

Zvimwe zvezvimiro zvechiratidzo chekutendeseka zvinosanganisira kurasikirwa kwekuisa, pedyo-kumagumo uye kure-kumagumo crosstalk, kudzoka kurasikirwa, skew kukanganisa mukati mekusiyana kwepairi, uye amplitude kubva kusiyanisa mode kusvika kune yakajairika mode. Kunyangwe zvinhu izvi zvakabatana uye zvichipesvedzerana, isu tinogona kufunga nezvechimwe nechimwe chinhu chimwe panguva kuti tidzidze maitiro ayo ekutanga.
Insertion Loss
Kurasikirwa kwekupinza ndiko kudzikisira kwechiratidzo cheamplitude kubva kumagumo ekutumira kusvika kumagumo ekugamuchira kwetambo, uye yakanangana nekuwanda. Kurasika kwekuisa zvakare kunoenderana newaya geji, sezvakaratidzwa mugirafu yekudzikisa pazasi. Kune zvemukati-zvipfupi zvemukati zvinoshandisa 30 kana 28-AWG tambo, tambo dzemhando yepamusoro dzinofanirwa kuve neattenuation isingasviki 2 dB/m pa1.5 GHz. Kune ekunze 6 Gb/s SAS uchishandisa tambo gumi, zvinokurudzirwa kushandisa tambo dzine avhareji waya geji yemakumi maviri nemana, ine attenuation ye13 dB chete pa3 GHz. Kana iwe uchida kuwana mamwe masaini magineti pamazinga epamusoro ekufambisa data, tsanangura tambo dzine yakaderera attenuation pakakwirira matambo etambo refu, seSFF-8482 ine SIMBA tambo kana SlimSAS SFF-8654 8i.

Crosstalk
Crosstalk inoreva huwandu hwesimba rinofambiswa kubva kune imwe chiratidzo kana mutsauko peya kuenda kune imwe chiratidzo kana musiyano peya. Kune tambo dzeSAS, kana iyo yepedyo-yekupedzisira crosstalk (NEXT) isiri diki zvakakwana, inokonzeresa mazhinji ematambudziko ekubatanidza. Chiyero cheNEXT chinongoitwa kune rumwe rutivi rwetambo, uye ihwo saizi yesimba rinotamiswa kubva kune yakabuda transmission signal pair kusvika kune yekupinza inogamuchira peya. Kuyerwa kwekure-end crosstalk (FEXT) kunoitwa nekupinza chiratidzo mukati mekutapurirana pair pane imwe mugumo wetambo uye nekucherechedza kuti ingani simba richiri kuchengetwa pachiratidzo chekutumira kune imwe mugumo wetambo. Iyo NEXT muzvikamu zvetambo uye zvibatanidza zvinowanzokonzerwa nekusagadzikana kuparadzaniswa kwechiratidzo chekusiyanisa peya, zvichida nekuda kwezvigadziko nemapulagi, kusina kukwana pasi, kana kubata kusina kunaka kwenzvimbo yekumisa tambo. Vagadziri veSistimu vanofanirwa kuve nechokwadi chekuti vasanganisi vetambo vakagadzirisa nyaya nhatu idzi, senge muzvikamu zvakaita seMINI SAS HD SFF-8644 kana OCuLink SFF-8611 4i.

24, 26 uye 28 ndiwo akajairwa 100Ω tambo kurasikirwa macurves.

Pamagungano emhando yepamusoro tambo, iyo NEXT yakayerwa zvinoenderana ne "SFF-8410 - Tsanangudzo yeHSS Copper Testing uye Performance Zvinodiwa" inofanirwa kunge yakaderera kupfuura 3%. Kana iri S-parameter, iyo NEXT inofanira kunge yakakura kupfuura 28 dB.
Dzorera kurasikirwa
Kurasikirwa kwekudzoka kunoyera ukuru hwesimba rinoratidzwa kubva kuhurongwa kana tambo kana chiratidzo chaiswa. Iri rinoratidzira simba rinokonzera kudzikira kweiyo siginecha amplitude painogashira tambo uye inogona kutungamira kune kusaina kutendeseka nyaya pakupera kwekutumira, izvo zvinozokonzeresa kukanganiswa kwemagetsi kune sisitimu nevagadziri vehurongwa.
Uku kurasikirwa kwekudzoka kunokonzerwa ne impedance mismatch muzvikamu zvetambo. Chete nekubata dambudziko iri nekuchenjerera ndipo iyo impedance haigone kuchinja kana chiratidzo chichipfuura nepakati pezvigadziko, mapulagi, uye tambo terminals, kuitira kuti uderedze iyo impedance mutsauko. Iyo yazvino SAS-4 yakajairwa inogadziridza iyo impedance kukosha kubva ± 10Ω muSAS-2 kusvika ± 3Ω. Tambo dzemhando yepamusoro dzinofanirwa kuchengetedza zvinodiwa mukati mekushivirira kwezita re85 kana 100 ± 3Ω, senge SFF-8639 ine SATA 15P kana MCIO 74 Pin Cable.

Skew kukanganisa
MuSAS tambo, kune marudzi maviri e skew kukanganisa: pakati pekusiyanisa pairi uye mukati mekusiyana kwepairi (chiratidzo chekuvimbika dzidziso - chiratidzo chekusiyanisa). Nechepfungwa, kana masaini akawanda akaiswa panguva imwe chete kumagumo etambo, anofanirwa kusvika kune imwe magumo panguva imwe chete. Kana zviratidzo izvi zvikasasvika panguva imwe chete, chiitiko ichi chinonzi cable skew distortion, kana kunonoka-skew kukanganisa. Pamapeya akasiyana-siyana, kukanganisa kwe skew mukati mekusiyana kwepairi ndiko kunonoka pakati pemakondakita maviri epairi yekusiyanisa, nepo kukanganisa kwe skew pakati pezviviri zvakasiyana ndiko kunonoka pakati pezvikamu zviviri zvezvikamu zvakasiyana. Yakakura skew kukanganisa mukati meiyo mutsauko vaviri inogona kukanganisa kusiyanisa chiyero cheiyo inofambiswa chiratidzo, kuderedza iyo chiratidzo amplitude, kuwedzera nguva jitter, uye kukonzera electromagnetic kukanganiswa matambudziko. Kune tambo dzemhando yepamusoro, iyo skew kukanganisa mukati meiyo mutsauko pairi inofanirwa kuve isingasviki gumi ps, senge SFF-8654 8i kusvika SFF-8643 kana Anti-misalignment Insertion tambo.
Electromagnetic interference
Pane zvakawanda zvinokonzeresa matambudziko ekukanganiswa kwemagetsi mumatambo: kusadzivirira kana kusadzivirira, nzira isiriyo yekumisa pasi, isina kuenzana masaini masaini, uyezve, impedance kusawirirana ndicho chikonzero. Kune tambo dzekunze, dziviriro uye pasi zvinogona kunge zviri zvinhu zviviri zvakakosha zvinofanirwa kugadziriswa, senge SFF-8087 ine red mesh kana Cooper mesh yekumisa tambo.
Kazhinji, kunze kana kwemagetsi kupindira kudzivirira kunofanirwa kuve kuviri kudzivirirwa kwesimbi foil uye yakarukwa dhizaini, ine yakazara yekuvhara inokwana 85%. Panguva imwecheteyo, kudzivirirwa uku kunofanira kubatanidzwa kune jekete rekunze rekubatanidza, ne 360 ​​° yakakwana. Kudzivirirwa kwemaviri ega ega ega ega kunofanirwa kuve kwakaparadzaniswa nekudzivirira kwekunze, uye mitsara yavo yekusefa inofanirwa kugumira pachiratidziro chehurongwa kana DC pasi kuti ive nechokwadi chekubatanidza impedance kudzora kwechibatanidza uye zvinhu zvetambo, seSFF-8654 8i Yakazara Wrap anti-slash kana Scoop-proof yekubatanidza tambo.