High-speed SAS Cables: Txuas thiab Teeb Pom Kev Zoo

High-speed SAS Cables: Txuas thiab Teeb Pom Kev Zoo

Teeb liab kev ncaj ncees Specifications

Qee qhov tseem ceeb ntawm cov teeb liab kev ncaj ncees muaj xws li kev poob qis, ze-kawg thiab deb-kawg crosstalk, rov qab poob, skew distortion nyob rau hauv sib txawv khub, thiab lub amplitude los ntawm txawv hom mus rau hom hom. Txawm hais tias cov xwm txheej no muaj kev cuam tshuam thiab cuam tshuam rau ib leeg, peb tuaj yeem xav txog txhua yam ntawm ib lub sijhawm los kawm txog nws qhov cuam tshuam loj.
Insertion Loss
Insertion poob yog qhov attenuation ntawm lub teeb liab amplitude los ntawm qhov kawg xa mus rau qhov kawg ntawm lub cable, thiab nws yog ncaj qha proportional rau zaus. Insertion poob kuj nyob ntawm qhov ntsuas hluav taws xob, raws li qhia hauv daim duab attenuation hauv qab no. Rau cov khoom siv luv luv uas siv 30 lossis 28-AWG cables, cov kab hluav taws xob zoo yuav tsum muaj qhov qis dua 2 dB / m ntawm 1.5 GHz. Rau sab nraud 6 Gb / s SAS siv 10m cables, nws raug nquahu kom siv cov cables nrog qhov ntsuas nruab nrab ntawm 24, uas muaj qhov attenuation ntawm 13 dB ntawm 3 GHz. Yog tias koj xav ua kom tiav cov teeb liab ntau dua ntawm cov ntaub ntawv hloov pauv ntau dua, qhia cov cables nrog qis attenuation ntawm high zaus rau cov cables ntev, xws li SFF-8482 nrog POWER cable lossis SlimSAS SFF-8654 8i.

Crosstalk
Crosstalk yog hais txog tus nqi ntawm lub zog uas kis tau los ntawm ib lub teeb liab lossis qhov sib txawv ntawm ib khub mus rau lwm lub teeb liab lossis qhov sib txawv. Rau SAS cables, yog tias qhov ze-kawg crosstalk (Tom ntej) tsis yog me me, nws yuav ua rau feem ntau ntawm cov teeb meem txuas. Kev ntsuas ntawm NEXT tsuas yog ua nyob rau ntawm ib kawg ntawm lub cable, thiab nws yog qhov loj ntawm lub zog xa tawm los ntawm qhov tso zis kis tau tus khub mus rau lub tswv yim tau txais khub. Kev ntsuas ntawm qhov deb-kawg crosstalk (FEXT) yog ua los ntawm kev txhaj tshuaj rau hauv qhov sib kis ntawm ib qho kawg ntawm lub cable thiab saib seb lub zog npaum li cas tseem khaws cia ntawm cov teeb liab kis ntawm lwm qhov kawg ntawm lub cable. Tom ntej no nyob rau hauv cable Cheebtsam thiab connectors feem ntau yog tshwm sim los ntawm tsis zoo cais ntawm lub teeb liab sib txawv khub, tejzaum nws yog vim lub qhov (sockets) thiab plugs, tsis tiav grounding, los yog tsis tsim nyog tuav ntawm lub cable termination cheeb tsam. Cov neeg tsim qauv yuav tsum tau xyuas kom meej tias cov khoom siv cable tau hais txog peb qhov teeb meem no, xws li hauv cov khoom xws li MINI SAS HD SFF-8644 lossis OCuLink SFF-8611 4i.

24, 26 thiab 28 yog qhov raug 100Ω cable poob nkhaus.

Rau cov khoom siv hluav taws xob zoo, NEXT ntsuas raws li "SFF-8410 - Specification rau HSS Copper Testing thiab Performance Requirements" yuav tsum qis dua 3%. Raws li rau S-parameter, NEXT yuav tsum siab dua 28 dB.
Rov qab poob
Rov qab poob ntsuas qhov loj ntawm lub zog cuam tshuam los ntawm lub kaw lus lossis cable thaum lub teeb liab raug txhaj. Qhov kev xav ntawm lub zog no ua rau txo qis ntawm cov teeb liab amplitude ntawm qhov kawg ntawm lub cable thiab tuaj yeem ua rau muaj teeb meem kev ncaj ncees ntawm qhov kawg, uas tuaj yeem ua rau muaj teeb meem electromagnetic cuam tshuam rau lub kaw lus thiab cov neeg tsim qauv.
Qhov kev poob rov qab no yog tshwm sim los ntawm impedance mismatch hauv cov khoom siv cable. Tsuas yog los ntawm kev kho qhov teeb meem no ua tib zoo ua kom lub impedance tsis hloov thaum lub teeb liab dhau los ntawm lub qhov (socket), plugs, thiab cable terminals, thiaj li txo qhov impedance variation. Tus qauv SAS-4 tam sim no hloov kho tus nqi impedance ntawm ± 10Ω hauv SAS-2 rau ± 3Ω. Cov kab hluav taws xob zoo yuav tsum tswj hwm qhov yuav tsum tau ua nyob rau hauv lub siab ntawm nominal 85 lossis 100 ± 3Ω, xws li SFF-8639 nrog SATA 15P lossis MCIO 74 Pin Cable.

Skew distortion
Hauv SAS cables, muaj ob hom skew distortion: ntawm cov khub sib txawv thiab nyob rau hauv cov khub sib txawv (cim qhia kev ntseeg siab - lub teeb liab sib txawv). Txoj kev xav, yog tias muaj ntau lub teeb liab tawm ib txhij ntawm ib kawg ntawm cable, lawv yuav tsum ncav cuag lwm qhov kawg ib txhij. Yog tias cov teeb liab tsis tuaj txog ib txhij, qhov tshwm sim no hu ua cable skew distortion, lossis ncua-skew distortion. Rau cov khub sib txawv, qhov skew distortion nyob rau hauv tus khub sib txawv yog qhov ncua ntawm ob tus neeg xyuas pib ntawm tus khub sib txawv, thaum lub skew distortion ntawm cov khub sib txawv yog qhov ncua ntawm ob pawg sib txawv. Loj skew distortion nyob rau hauv cov sib txawv khub tuaj yeem ua rau qhov sib txawv ntawm qhov sib txawv ntawm cov teeb liab kis tau tus mob, txo cov teeb liab amplitude, nce lub sij hawm jitter, thiab ua rau muaj teeb meem electromagnetic cuam tshuam. Rau cov kab hluav taws xob zoo, qhov sib txawv ntawm qhov sib txawv ntawm qhov sib txawv yuav tsum tsawg dua 10 ps, ​​xws li SFF-8654 8i rau SFF-8643 lossis Anti-misalignment Insertion cable.
Electromagnetic cuam tshuam
Muaj ntau yam ua rau muaj teeb meem ntawm electromagnetic cuam tshuam hauv cov cables: kev tiv thaiv tsis zoo los yog tsis muaj kev tiv thaiv, txoj hauv kev tsis raug, tsis muaj qhov sib txawv ntawm qhov sib txawv, thiab ntxiv mus, impedance mismatch kuj yog qhov ua rau. Rau cov cables sab nraud, kev tiv thaiv thiab hauv av yuav yog ob qho tseem ceeb tshaj plaws uas yuav tsum tau hais txog, xws li SFF-8087 nrog liab mesh lossis Cooper mesh grounding cable.
Feem ntau, kev cuam tshuam sab nraud lossis electromagnetic cuam tshuam yuav tsum yog ob lub thaiv ntawm cov ntawv hlau thiab cov txheej braided, nrog rau tag nrho cov kev pab cuam tsawg kawg yog 85%. Nyob rau tib lub sijhawm, qhov kev tiv thaiv no yuav tsum tau txuas nrog lub tsho sab nrauv ntawm lub connector, nrog rau kev sib txuas ua tiav 360 °. Kev tiv thaiv ntawm ib tus neeg sib txawv yuav tsum raug cais tawm ntawm kev tiv thaiv sab nraud, thiab lawv cov kab lim dej yuav tsum tau txiav tawm ntawm qhov system teeb liab lossis DC hauv av kom ntseeg tau tias kev sib koom ua ke ntawm cov khoom sib txuas thiab cov khoom siv cable, xws li SFF-8654 8i Full Wrap anti-slash lossis Scoop-proof connector cable.