9.4.4Electrical description

SAS drives use the device connector for:

DC power

SAS interface

Activity LED

This connector is designed to either plug directly into a backpanel or accept cables.

9.4.5Pin descriptions

This section provides a pin-out of the SAS device and a description of the functions provided by the pins.

Table 15: SAS pin descriptions

Pin

Signal name

Signal type

 

 

 

 

 

 

S1

Port A Ground

 

 

 

 

S2*

+Port A_in

Diff. input pair

 

 

 

S3*

-Port A_in

 

 

 

 

S4

Port A Ground

 

 

 

 

S5*

-Port A_out

Diff output pair

 

 

 

S6*

+Port A_out

 

 

 

 

S7

Port A Ground

 

 

 

 

S8

Port B Ground

 

 

 

 

S9*

+Port B_in

Diff. input pair

 

 

 

S10*

-Port B_in

 

 

 

 

S11

Port A Ground

 

 

 

 

S12*

-Port B_out

Diff output pair

 

 

 

S13*

+Port B_out

 

 

 

 

S14

Port B Ground

 

 

 

 

 

 

 

*- Short pin to support hot plugging NC - No connection in the drive.

Pin

Signal name

Signal type

 

 

 

 

 

 

P1*

NC (reserved 3.3Volts)

 

 

 

 

P2*

NC (reserved 3.3Volts)

 

 

 

 

P3

NC (reserved 3.3Volts)

 

 

 

 

P4

Ground

 

 

 

 

P5

Ground

 

 

 

 

P6

Ground

 

 

 

 

P7

5 Volts charge

 

 

 

 

P8*

5 Volts

 

 

 

 

P9*

5 Volts

 

 

 

 

P10

Ground

 

 

 

 

P11*

Ready LED

Open collector out

 

 

 

P12

Ground

 

 

 

 

P13

12 Volts charge

 

 

 

 

P14*

12 Volts

 

 

 

 

P15*

12 Volts

 

 

 

 

60

Cheetah T10 SAS Product Manual, Rev. A

Page 66
Image 66
Seagate ST3146755SS manual Electrical description, Pin descriptions, SAS pin descriptions, Pin Signal name Signal type

ST3300555SS, ST3146755SS, ST373355SS specifications

The Seagate ST373355SS, ST3146755SS, and ST3300555SS represent a range of high-performance hard drives designed for enterprise applications, particularly in server environments requiring reliability, speed, and high capacity.

The ST373355SS is a 73.5 GB SCSI hard drive operating at 15,000 RPM, which ensures rapid data access and superior performance, making it ideal for transactional applications and data-intensive tasks. With its 4 MB cache, the drive leverages fast read and write speeds, enhancing overall system responsiveness. The SCSI interface, operating at 80 MB/s, allows for high-speed data transfers, making it a suitable choice for demanding environments where quick access to information is critical. Its hot-swappable feature enables maintenance without shutting down the system, maximizing uptime and productivity.

The ST3146755SS, with a capacity of 146.8 GB, builds on the performance of its predecessor while introducing improvements in data handling and reliability. Operating at the same impressive 15,000 RPM, this model also features a 16 MB cache that greatly improves data throughput and access speed. The drive is designed to reduce latency, which is crucial for applications where timing is everything. It is equipped with advanced error recovery features and Seagate’s innovative PowerTrim technology, which improves power efficiency during read and write operations. The ST3146755SS also features a higher mean time between failures (MTBF), underscoring its reliability in high-demand environments.

Lastly, the ST3300555SS offers even greater capacity with 300 GB. This drive maintains the 15,000 RPM rotation speed and benefits from a 16 MB cache, providing a balance of speed and storage capacity. Its advanced SCSI interface supports not just speed but also data integrity, ensuring consistent performance during extensive data transfers. The drive is designed to handle workloads naturally associated with enterprise servers, data warehouses, and video editing applications. Its rugged build supports continuous operation and is tested for high-temperature environments to ensure durability.

In summary, the Seagate ST373355SS, ST3146755SS, and ST3300555SS hard drives are engineered for enterprise environments, combining impressive RPM speeds, significant storage capacities, and advanced technologies to deliver reliability, performance, and efficiency for critical applications. These hard drives represent Seagate's commitment to providing solutions that meet the rigorous demands of modern data environments.