Seagate ST1000NX0373 ユーザーズマニュアル

Seagate Enterprise Capacity 2.5 HDD v3 SAS Product Manual, Rev. D

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The Ready LED Out signal is designed to pull down the cathode of an LED. The anode is attached to the proper +3.3 volt supply through 
an appropriate current limiting resistor. The LED and the current limiting resistor are external to the drive. See the next table for the output 
characteristics of the LED drive signals.  

The drive SAS differential signals comply with the intra-enclosure (internal connector) requirements of the SAS standard.

The table below defines the general interface characteristics

Seagate SAS-3 compatible drives are compliant with the latest SAS-3 Specification (T10/BSR INCITS 519 rev. 06).

The main difference from SAS-2 is the Tx and Rx training that allows the host and drive to adjust the amplitude and emphasis values to the 
channel. The receiver still employs Decision Feedback Equalizer (DFE) and Feed Forward Equalizer (FFE) circuitry to accomplish this 
training. 

Please contact the Seagate representative for SAS electrical details, if required.

For more information about the Phy, Link, Transport, and Applications layers of the SAS interface, refer to the Seagate SAS Interface 
Manual

, part number 100293071.

For more information about the SCSI commands used by Seagate SAS drives, refer to the Seagate SCSI Commands Reference Manual, 
part number 100293068.

LED off, high

0 V 

£

 VOH 

£

 3.6 V

-100 μA < I

OH

 < 100 μA

LED on, low

I

OL

 = 15 mA

0 

£

 V

OL

 

£

 0.225 V

Bit rate (nominal)

Mbaud

3,000

6,000

12,000

Unit interval (UI)(nominal)

ps

333.3

166.6

83.3

Impedance (nominal, differential )

ohm

100

100

100

Transmitter transients, maximum

V

± 1.2

± 1.2

± 1.2

Receiver transients, maximum

V

± 1.2

± 1.2

± 1.2