Seagate ST1200MM0017 ユーザーズマニュアル

S

EAGATE 

E

NTERPRISE 

P

ERFORMANCE 

10K HDD 

V

7  P

RODUCT 

M

ANUAL

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EV

. C

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A typical SAS differential copper transmitter and receiver pair is shown in Figure 13. The receiver is AC coupling to eliminate 
ground shift noise. 

The drive receives power (+5 volts and +12 volts) through the SAS device connector. 

Three +12 volt pins provide power to the drive, 2 short and 1 long. The current return for the +12 volt power supply is through 
the common ground pins. The supply current and return current must be distributed as evenly as possible among the pins. 

Three +5 volt pins provide power to the drive, 2 short and 1 long. The current return for the +5 volt power supply is through 
the common ground pins. The supply current and return current must be distributed as evenly as possible among the pins. 

Current to the drive through the long power pins may be limited by the system to reduce inrush current to the drive during hot 
plugging. 

This section describes the electrical signal characteristics of the drive’s input and output signals. See Section 11.4.5 for 
signal type and signal name information.

The Ready LED Out signal is driven by the drive as indicated in the table below.

Ready LED Meaning bit mode page 19h

0

1

Spun down and no activity

Off

Off

Spun down and activity (command executing)

On

On

Spun up and no activity

On

Off

Spun up and activity (command executing)

Off

On

Spinning up or down

Blinks steadily

(50% on and 50% off, 0.5 seconds on and off for 0.5 seconds)

Format in progress, each cylinder change

Toggles on/off