Single-ended I/O cable pin assignments for LW drives are shown in Table 15.

Single-ended I/O pin assignments for LC models are shown in Table 16. The LC model does not require an I/O cable. It is designed to connect directly to a back panel connector.

9.7.1.3Cables for low voltage differential drivers/receivers

The SPI-3 and SPI-4 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 19 and 20 for examples of recommended SCSI LVD cable types and lengths.

It should be noted from the data in Tables 19 and 20 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 20.

Table 19:

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

 

 

 

 

 

 

 

 

 

 

 

Single-

Single-

 

Conductor

 

 

 

Differential

ended

ended

Time

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

 

 

 

 

 

 

 

 

82

Cheetah 10K.7 SCSI Product Manual, Rev. D

Page 91 Page 93
Page 92
Image 92
Seagate ST373207LW/LC, ST3146707LW/LC, ST3300007LW/LC manual Cables for low voltage differential drivers/receivers
Page 91 Page 93

ST3300007LW/LC, ST373207LW/LC, ST3146707LW/LC specifications

Seagate's ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC are part of the company's renowned line of hard disk drives (HDDs), specifically designed for enterprise and high-performance computing environments. With their reliability and performance, these drives have become popular choices for data centers and critical applications requiring extensive storage capabilities.

One of the standout features of these models is their capacity to handle large volumes of data. The ST3146707LW/LC has a capacity of 146GB, while the ST373207LW/LC offers 73GB, and the ST3300007LW/LC comes with a substantial 300GB. These capacities make them well-suited for applications that require not only high storage space but also rapid access to data.

In terms of performance, these drives utilize a 10,000 RPM spindle speed, which significantly enhances data access times and overall performance. The combination of fast rotational speeds with Seagate's advanced caching algorithms allows for swift data retrieval, making these drives ideal for environments where speed is crucial.

These HDDs also employ the SCSI (Small Computer System Interface) interface, which promises high data transfer rates and reliability in enterprise-level applications. The Ultra320 SCSI interface can support transfer rates up to 320 MB/s, ensuring that the drives can efficiently communicate with other system components.

Another key technology featured in these models is Seagate's Adaptive Error Correction technology, which enhances data integrity and reliability. This feature helps in the detection and correction of errors that can occur during data transfer, reducing the risk of data loss.

Performance consistency is critical in enterprise environments, and these drives are built to endure the demands of 24/7 operation. They are designed with robust mechanisms to withstand temperature fluctuations, shock, and vibrations commonly found in data center settings.

In summary, the Seagate ST3146707LW/LC, ST373207LW/LC, and ST3300007LW/LC hard drives exemplify advanced features and technologies tailored for enterprise storage solutions. With significant capacities, impressive spindle speeds, SCSI connectivity, and reliability-focused technologies, these drives remain a valuable asset for businesses relying on stable and high-performance data storage.
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