Seagate ST336605LW/LC/LCV manual Cables for low voltage differential drivers/receivers

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Cheetah 73LP Product Manual, Rev. E

Single-ended I/O pin assignments for LC models are shown in Table 14. The LC model does not require an I/O cable. It is designed to connect directly to a backpanel connector.

9.7.1.3Cables for low voltage differential drivers/receivers

The SPI-3 specification for differential impedance for LVD cables is 122.5 ± 12.5 ohms.

The maximum SCSI bus length between the terminators for a SCSI LVD point-to-point system (one initiator and one target) is 25 meters (82 feet).

The maximum SCSI bus length between the terminators for a SCSI LVD multidrop system (up to 16 total SCSI devices) is 12 meters (39.37 feet). However, implementation of this 12-meter total length is dependent on the configuration of the system and the choice of cable. See Tables 17 and 18 for examples of recommended SCSI LVD cable types and lengths.

It should be noted from the data in Tables 17 and 18 that shielded round twisted-pair cables can be used to implement a 12-meter system, while twist-n-flat cables cannot be used to implement a 12-meter system due to higher levels of attenuation and crosstalk. In addition, twist-n-flat cables with shorter sections of twist allow greater crosstalk and their lengths must be reduced as shown in Table 18.

Table 17:

Example shielded round twisted-pair cables—into a multi-drive backplane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Differential

 

Single-ended

Single-ended

Time

 

Conductor DC

Maximum shielded round

Cable

 

impedance,

 

impedance,

 

capacitance,

delay,

 

resistance,

 

twisted-pair cable length

description

 

nominal

 

nominal

 

maximum

 

nominal

 

nominal

 

for U160/U320

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

30 AWG

 

130 ohms

 

90 ohms

 

17 pF/ft

 

1.36 ns/ft

 

0.113 ohms/ft

12 meters minus the SCSI

solid

 

 

 

 

 

 

 

 

 

 

 

 

trace length of the backplane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

28 AWG

 

123 ohms

 

80 ohms

 

19 pF/ft

 

1.54 ns/ft

 

0.067 ohms/ft

12 meters minus the SCSI

stranded

 

 

 

 

 

 

 

 

 

 

 

 

trace length of the backplane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

28 AWG

 

132 ohms

 

85 ohms

 

20 pF/ft

 

1.50 ns/ft

 

0.065 ohms/ft

12 meters minus the SCSI

stranded

 

 

 

 

 

 

 

 

 

 

 

 

trace length of the backplane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Table 18:

Example twist-n-flat cables—into a multi-drive backplane

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Maximum

 

 

 

 

 

 

 

 

 

 

 

 

 

 

twist-n-flat

 

 

 

Differential

Single-ended

Single-ended

 

Time

 

Conductor DC

cable length

 

 

 

impedance,

impedance,

capacitance,

 

delay,

 

resistance,

for U160

Cable description

nominal

nominal

maximum

 

nominal

 

nominal

transfer rate

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TPE, 22.25" twist, 1.75"

131 ohms

93 ohms

15.3 pF/ft

 

1.45 ns/ft

 

0.105 ohms/ft

6.1 meters

flat, (24" flat to flat), 30

 

 

 

 

 

 

 

 

 

 

 

(20.0 feet)

AWG solid tinned copper

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TPE, 8.1" twist, 1.75" flat,

131 ohms

93 ohms

15.3 pF/ft

 

1.45 ns/ft

 

0.105 ohms/ft

4.9 meters

(9.85" flat to flat), 30 AWG

 

 

 

 

 

 

 

 

 

 

 

(16.66 feet)

solid tinned copper

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TPE, 4.25" twist, 1.75"

131 ohms

93 ohms

15.3 pF/ft

 

1.45 ns/ft

 

0.105 ohms/ft

3.04 meters

flat, (6" flat to flat), 30

 

 

 

 

 

 

 

 

 

 

 

(10.0 feet)

AWG solid tinned copper

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

9.8Terminator requirements

Caution: These drives do not have onboard internal terminators. The user, systems integrator or host equip- ment manufacturer must provide a terminator arrangement external to the drive when termination is required. For LW/LWV drives, use terminator modules that plug between the SCSI I/O cable and the drive I/O connector or on the end of a short I/O cable stub extending past the last cable connec- tor. LC/LCV drives are designed to be plugged into a backpanel connector without cabling.

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Contents ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page Revision status summary sheet Revision Date Writer/Engineer Sheets AffectedPage Contents Defect and error management InstallationSeagate Technology support services Interface requirementsList of Figures Cheetah 73LP Product Manual, Rev. E ViiPage Scope Cheetah 73LP family drive ST373405LW shownCheetah 73LP Product Manual, Rev. E Applicable standards and reference documentation Korean MIC Australian C-TickTaiwanese Bsmi General description Cheetah 73LP family drive Cheetah 73LP Product Manual, Rev. E Standard features Media characteristicsPerformance ReliabilityFactory installed accessories Options factory installedAccessories user installed Unformatted and formatted capacitiesPerformance characteristics Start/stop time Ultra2 Scsi Ultra3 ScsiPrefetch/multi-segmented cache control Cheetah 73LP Product Manual, Rev. E Cache operation Caching write dataPrefetch operation Reliability specifications Reliability and service Preventive maintenanceService life Service philosophy7 S.M.A.R.T Controlling S.M.A.R.TPerformance impact MillisecondsReporting control Determining rateState of the drive prior to testing DST Failure DefinitionImplementation Invoking DSTShort and extended tests Short test Function Code 001bExtended test Function Code 010b Log page entriesShipping Cheetah 73LP Product Manual, Rev. E Product warrantyProduct repair and return information Cheetah 73LP Product Manual, Rev. E AC power requirements Physical/electrical specificationsDC power requirements Conducted noise immunity Power sequencing3 12 V Current profile Typical ST336605 drive +12 V current profile Typical ST336605 drive +5 V current profile Amperes 000 900 800 700 600 Temperature Cheetah 73LP Product Manual, Rev. E Environmental limitsRelative humidity Effective altitude sea levelShock and vibration ShockRecommended mounting Vibration Air cleanlinessAcoustics LW and LWV mounting configuration dimensions LC and LCV mounting configuration dimensions Drive error recovery procedures Defect and error managementDrive internal defects Scsi systems errors Installation Configure drive optionsFormatting Drive ID/option select headerDo not install jumpers retain cover J5 jumper header on LW/LWV models only J2 option select header Cheetah 73LP Product Manual, Rev. E Function description Does not apply to LC/LCV modelDrive orientation CoolingCheetah 73LP Product Manual, Rev. E Drive mounting GroundingCheetah 73LP Product Manual, Rev. E Interface requirements Scsi interface messages supportedScsi interface commands supported Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Inquiry Vital Product data Mode Sense data DEF CHG Cheetah 73LP Product Manual, Rev. E Condition/feature supported by 2 REQ/ACK offset DC cable and connectorPhysical interface Pin Power Scsi interface physical description Scsi interface cable requirementsMating connectors Mating connectors for LW and LWV model drivesMating connectors for LC and LCV model drives ST373405LC/LCV and ST336605LC/LCVCheetah 73LP Product Manual, Rev. E Right-angle to Pcba connectors Scsi ID650±.005 155 100 346 Front View GND +DBP1 62Cheetah 73LP Product Manual, Rev. E REQ +REQ Electrical description LVD output characteristicsMultimode-SE and LVD alternatives General cable characteristics Single-ended drivers/receiversCables for low voltage differential drivers/receivers Terminator requirementsLC and LCV drives Disc drive Scsi timing Spindle status Command status LED status Drive activity LEDCheetah 73LP Product Manual, Rev. E Seagate Technology support services Online Services Automated ServicesPresales Support Technical SupportUSA/Canada/Latin America Support Services Customer Service CSOEuropean Support Services Asia/Pacific Support Services Africa/Middle East Support ServicesCall Center Toll-free Direct dial Cheetah 73LP Product Manual, Rev. E Index Cheetah 73LP Product Manual, Rev. E Cheetah 73LP Product Manual, Rev. E Scam Scsi Scsi ID 80Cheetah 73LP Product Manual, Rev. E
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