Seagate ST373405LW/LWV/LC/LCV manual General cable characteristics, Single-ended drivers/receivers

Page 75

Cheetah 73LP Product Manual, Rev. E

65

LVD input characteristics

Each differential signal received by LVD interface receiver circuits shall have the following input characteristics when measured at the disc drive connector:

Steady state Low level input differential voltage = 0.030 V = < Vin = < 3.6 V (signal negation/logic 0) Steady state High level input differential voltage = –3.6 V = < Vin = < –0.030 V (signal assertion/logic 1) Differential voltage = +0.030 V minimum with common-mode voltage range 0.845 V = < Vcm = < 1.655 V. (T10/1302D revision 14, section A.3.2).

 

VCCA

 

VCCB

Single

LVD Signal Drivers

Single

Single

 

Ended

 

Ended

Ended

Circuitry

 

Receiver

Negation

 

LVD

 

Driver

 

 

 

 

Receiver

 

 

Single

 

 

Single

Ended

 

 

Ended

Ground

 

 

Assertion

Driver

 

 

Driver

 

LVD Signal Drivers

 

 

Ground

 

 

 

Single Ended:

GND

—Signal

LVD:

+Signal

—Signal

Figure 24. Typical SE-LVD alternative transmitter receiver circuits

9.7.1.1General cable characteristics

To minimize discontinuities and signal reflections, cables of different impedances should not be used in the same bus. Implementations may require trade-offs in shielding effectiveness, cable length, the number of loads, transfer rates, and cost to achieve satisfactory system operation. If shielded and unshielded cables are mixed within the same SCSI bus, the effect of impedance mismatch must be carefully considered. Proper impedance matching is especially important in order to maintain adequate margin at fast SCSI transfer rates.

9.7.1.2Single-ended drivers/receivers

The maximum total cable length allowed with drives using single-ended I/O driver and receiver circuits depends on several factors. Table 16 lists the maximum lengths allowed for different configurations of drive usage. These values are from the SPI documents. All device I/O lines must have equal to or less than 25 pf capacitance to ground, measured at the beginning of the stub.

Table 16: Cable characteristics for single-ended circuits

 

Maximum number of

Maximum length between

Transmission line impedance

 

 

 

I/O transfer rate

devices on the bus

SCSI SE terminators

REQ/ACK

Other signals

 

 

 

 

 

 

 

 

 

 

<10M transfers/s (Fast 10)

16 (wide SCSI bus)

3 meters (9.8 feet)

90 + 6 Ohms

90 + 10 Ohms

 

 

 

 

 

<20M transfers/s (Fast 20)

4 (wide SCSI bus)

3 meters (9.8 feet)

90 + 6 Ohms

90 + 10 Ohms

 

 

 

 

 

<20M transfers/s (Fast 20)

8 (wide SCSI bus)

1.5 meters (4.9 feet)

90 + 6 Ohms

90 + 10 Ohms

 

 

 

 

 

A stub length of no more than 0.1 meter (0.33 foot) is allowed off the mainline interconnection with any con- nected equipment. The stub length is measured from the transceiver to the connection to the mainline SCSI bus.

Single-ended I/O cable pin assignments for LW drives are shown in Table 13.

Page 74 Page 76
Image 75
Page 74 Page 76
Contents ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page ST373405LW/LWV/LC/LCV ST336605LW/LC/LCV Page Revision Date Writer/Engineer Sheets Affected Revision status summary sheetPage Contents Interface requirements Defect and error managementInstallation Seagate Technology support servicesCheetah 73LP Product Manual, Rev. E Vii List of FiguresPage Cheetah 73LP family drive ST373405LW shown ScopeCheetah 73LP Product Manual, Rev. E Applicable standards and reference documentation Australian C-Tick Korean MICTaiwanese Bsmi General description Cheetah 73LP family drive Reliability Cheetah 73LP Product Manual, Rev. E Standard featuresMedia characteristics PerformanceUnformatted and formatted capacities Factory installed accessoriesOptions factory installed Accessories user installedPerformance characteristics Ultra2 Scsi Ultra3 Scsi Start/stop timePrefetch/multi-segmented cache control Caching write data Cheetah 73LP Product Manual, Rev. E Cache operationPrefetch operation Reliability specifications Service philosophy Reliability and servicePreventive maintenance Service lifeControlling S.M.A.R.T 7 S.M.A.R.TDetermining rate Performance impactMilliseconds Reporting controlInvoking DST State of the drive prior to testingDST Failure Definition ImplementationLog page entries Short and extended testsShort test Function Code 001b Extended test Function Code 010bCheetah 73LP Product Manual, Rev. E Product warranty ShippingProduct repair and return information Cheetah 73LP Product Manual, Rev. E Physical/electrical specifications AC power requirementsDC power requirements Power sequencing Conducted noise immunity3 12 V Current profile Typical ST336605 drive +12 V current profile Typical ST336605 drive +5 V current profile Amperes 000 900 800 700 600 Effective altitude sea level TemperatureCheetah 73LP Product Manual, Rev. E Environmental limits Relative humidityShock Shock and vibrationRecommended mounting Air cleanliness VibrationAcoustics LW and LWV mounting configuration dimensions LC and LCV mounting configuration dimensions Defect and error management Drive error recovery proceduresDrive internal defects Scsi systems errors Drive ID/option select header InstallationConfigure drive options FormattingDo not install jumpers retain cover J5 jumper header on LW/LWV models only J2 option select header Does not apply to LC/LCV model Cheetah 73LP Product Manual, Rev. E Function descriptionCooling Drive orientationGrounding Cheetah 73LP Product Manual, Rev. E Drive mountingCheetah 73LP Product Manual, Rev. E Scsi interface messages supported Interface requirementsScsi 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 DC cable and connector 2 REQ/ACK offsetPhysical interface Pin Power Scsi interface cable requirements Scsi interface physical descriptionST373405LC/LCV and ST336605LC/LCV Mating connectorsMating connectors for LW and LWV model drives Mating connectors for LC and LCV model drivesCheetah 73LP Product Manual, Rev. E Scsi ID Right-angle to Pcba connectors650±.005 155 100 346 Front View GND +DBP1 62Cheetah 73LP Product Manual, Rev. E REQ +REQ LVD output characteristics Electrical descriptionMultimode-SE and LVD alternatives Single-ended drivers/receivers General cable characteristicsTerminator requirements Cables for low voltage differential drivers/receiversLC and LCV drives Disc drive Scsi timing Drive activity LED Spindle status Command status LED statusCheetah 73LP Product Manual, Rev. E Technical Support Seagate Technology support services Online ServicesAutomated Services Presales SupportCustomer Service CSO USA/Canada/Latin America Support ServicesEuropean Support Services Africa/Middle East Support Services Asia/Pacific 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
Top Page Image Contents