Iintambo ze-SAS ezinesantya esiphezulu: Iziqhagamshelo kunye nokuPhuculwa kweMiqondiso

Iintambo ze-SAS ezinesantya esiphezulu: Iziqhagamshelo kunye nokuPhuculwa kweMiqondiso

IiNkcazelo zeMfezeko yoMqondiso

Ezinye zeeparameters eziphambili zengqibelelo yesignali zibandakanya ukulahlekelwa kokufaka, i-crosstalk esondeleyo kunye ne-de-end, i-back-back back, ukuphazamiseka kwe-skew ngaphakathi kweebini ezihlukeneyo, kunye ne-amplitude ukusuka kwimodi yokwahlukana ukuya kwimodi eqhelekileyo. Nangona ezi zinto zinxibelelene kwaye zinefuthe omnye komnye, sinokuqwalasela into nganye ngexesha ukuze sifunde impembelelo yayo ephambili.
Ilahleko yokuFaka
Ilahleko yokufaka i-attenuation ye-signal amplitude ukusuka ekupheleni kokuthumela ukuya ekupheleni kokufumana intambo, kwaye ihambelana ngokuthe ngqo kwi-frequency. Ilahleko yokufaka nayo ixhomekeke kwigeyiji yocingo, njengoko kubonisiwe kwigrafu yokuthomalalisa engezantsi. Kuluhlu olufutshane lwamacandelo angaphakathi usebenzisa i-30 okanye i-28-AWG iintambo, iintambo ezikumgangatho ophezulu kufuneka zibe ne-attenuation engaphantsi kwe-2 dB / m kwi-1.5 GHz. Kwi-6 Gb / s SAS yangaphandle usebenzisa iintambo ze-10m, kucetyiswa ukuba kusetyenziswe iintambo ezinomlinganiselo we-wire gauge ye-24, ene-attenuation ye-13 dB kuphela kwi-3 GHz. Ukuba ufuna ukufezekisa umda wesignali ongaphezulu kumazinga aphezulu odluliselo lwedatha, cacisa iintambo ezinokunciphisa okusezantsi kwifrikhwensi ephezulu yeentambo ezinde, ezifana ne-SFF-8482 ngentambo AMANDLA okanye i-SlimSAS SFF-8654 8i.

Crosstalk
I-Crosstalk ibhekisa kumthamo wamandla ogqithiswa ukusuka kwisignali enye okanye isibini esahlukileyo ukuya kwesinye isignali okanye isibini esahlukileyo. Kwiintambo ze-SAS, ukuba i-crosstalk esondeleyo (i-NEXT) ayincinci ngokwaneleyo, iya kubangela uninzi lweengxaki zekhonkco. Umlinganiselo we-NEXT uqhutyelwa kuphela ekupheleni kwesinye intambo, kwaye ubukhulu bamandla adluliselwe kwi-output transmission pair pair to the input receive pair. Umlinganiselo we-inter-end crosstalk (FEXT) uqhutyelwa ngokujova isignali kwisibini sokuhambisa kwelinye icala lentambo kunye nokujonga ukuba angakanani amandla asele egcinwe kwisignali yokuhambisa kwelinye icala lentambo. OKULANDELAYO kumacandelo ekhebula kunye neziqhagamshelo zidla ngokubangelwa kukungahlulwa kakuhle kwesibini sokuhlukanisa isignali, mhlawumbi ngenxa yeesokethi kunye neeplagi, ukubekwa komhlaba okungaphelelanga, okanye ukuphathwa ngendlela engafanelekanga kwendawo yokuphelisa intambo. Abaqulunqi benkqubo kufuneka baqinisekise ukuba abahlanganisi bekhebula baye bajongana nale miba mithathu, njengakumacandelo afana ne-MINI SAS HD SFF-8644 okanye i-OCuLink SFF-8611 4i.

I-24, i-26 kunye ne-28 yi-100Ω i-cable loss curves eqhelekileyo.

Kwiindibano zekhebula ezikumgangatho ophezulu, i-NEXT ilinganiswe ngokuhambelana ne- "SFF-8410 - Ukucaciswa kwe-HSS Copper Testing and Performance Requirements" kufuneka ibe ngaphantsi kwe-3%. Ngokuphathelele i-S-parameter, OKULANDELAYO kufuneka ibe nkulu kuno-28 dB.
Buyisela ilahleko
Ukulinganisa ilahleko yokubuyisela ubukhulu bamandla abonakaliswe kwisistim okanye intambo xa umqondiso utofwa. La mandla abonakalisiweyo abangela ukuhla kwe-amplitude yomqondiso ekupheleni kokufumana intambo kwaye kunokukhokelela kwimiba yengqibelelo yomqondiso ekupheleni kokuhambisa, nto leyo enokubangela iingxaki zokuphazamiseka kombane wenkqubo kunye nabayili benkqubo.
Le lahleko ibuyayo ibangelwa kukungahambelani kwe-impedance kumacandelo entambo. Kuphela ngokuphatha le ngxaki ngononophelo olunokuthi i-impedance ingatshintshi xa isignali idlula kwiisokethi, iiplagi, kunye nee-terminal terminals, ukwenzela ukunciphisa ukuhluka kwe-impedance. Umgangatho wangoku we-SAS-4 uhlaziya ixabiso le-impedance ukusuka kwi-±10Ω kwi-SAS-2 ukuya kwi-±3Ω. Iintambo zomgangatho ophezulu kufuneka zigcine imfuno ngaphakathi kokunyamezela kwe-nominal 85 okanye i-100 ± 3Ω, njenge-SFF-8639 kunye ne-SATA 15P okanye i-MCIO 74 Pin Cable.

Skew ukugqwetheka
Kwiintambo ze-SAS, kukho iindidi ezimbini ze-skew distortion: phakathi kwababini abahlukeneyo kunye nangaphakathi kweebini ezihlukeneyo (ithiyori yengqibelelo yesiginali - isignali eyahlukileyo). Ngokwethiyori, ukuba iimpawu ezininzi zifakwa ngaxeshanye kwelinye icala lentambo, kufuneka zifike kwelinye icala ngaxeshanye. Ukuba le miqondiso ayifiki ngaxeshanye, le nto ibizwa ngokuba yi-cable skew distortion, okanye ukulibaziseka-skew distortion. Ngamabini ahlukeneyo, ukuguqulwa kwe-skew ngaphakathi kwebini yokwahlukana kukulibaziseka phakathi kwabaqhubi ababini besibini esahlukileyo, ngelixa ukuguqulwa kwe-skew phakathi kwababini abahlukeneyo kukulibaziseka phakathi kweeseti ezimbini zokwahlukana. Ukugqwetheka okukhulu kwe-skew ngaphakathi kwesibini esahlukileyo kunokonakalisa ibhalansi eyahlukileyo yomqondiso ogqithisiweyo, ukunciphisa i-amplitude yesignali, ukwandisa ixesha le-jitter, kwaye kubangele iingxaki zokuphazamiseka kwe-electromagnetic. Kwiintambo ezikumgangatho ophezulu, ukuguqulwa kwe-skew ngaphakathi kwibini ehlukeneyo kufuneka ibe ngaphantsi kwe-10 ps, ​​njenge-SFF-8654 8i ukuya kwi-SFF-8643 okanye i-Anti-misalignment Insertion cable.
Ukuphazamiseka kombane
Zininzi oonobangela beengxaki zophazamiseko lwe-electromagnetic kwiintambo: ukungakhuseleki kakuhle okanye ukungakhuseli, indlela engachanekanga yokubeka phantsi komhlaba, imiqondiso engalungelelananga yomahluko, nangaphezulu, ukungahambelani kwe-impedance ikwangunobangela. Kwiintambo zangaphandle, ukukhuselwa kunye nokubeka umhlaba kusenokwenzeka ukuba zezona zinto zimbini zibalulekileyo ekufuneka ziqwalaselwe, njenge-SFF-8087 enemesh ebomvu okanye i-Cooper mesh intambo yokumisa.
Ngokwesiqhelo, isikhuselo sophazamiseko sangaphandle okanye sombane kufuneka sibe sisikhuselo esiphindwe kabini sefoyile yesinyithi kunye nomaleko olulukiweyo, kunye nokugqunywa okupheleleyo okungama-85%. Ngexesha elifanayo, olu khuselo lufanele ludibaniswe nejacket yangaphandle yekhonkco, kunye ne-360 ° epheleleyo. Ukukhusela izibini ezihlukeneyo ezihlukeneyo kufuneka zibe zodwa kwisikhuselo sangaphandle, kwaye imigca yazo yokucoca kufuneka iphele kwisignali yenkqubo okanye kumhlaba we-DC ukuze kuqinisekiswe ulawulo oludibeneyo lwe-impedance ye-connector kunye namacandelo ekhebula, njenge-SFF-8654 8i Ukusonga ngokupheleleyo kwe-anti-slash okanye i-Scoop-proof connector cable.