Seagate Exos 7E8 SAS Product Manual, Rev. A
24
6.2
AC power requirements
None.
6.3
DC power requirements
The voltage and current requirements for a single drive are shown below. Values indicated apply at the drive connector.
[1]
Measured with average reading DC ammeter. Instant12V current peaks will exceed these values. Power supply at nominal voltage. N
(number of drives tested) = 6, 35 Degrees C ambient.
[2]
For +12 V, a –10% tolerance is allowed during initial spindle start but must return to ± 5% before reaching 7200 RPM. The ± 5% must be main-
tained after the drive signifies that its power-up sequence has been completed and that the drive is able to accept selection by the host initia-
tor.
[3]
See +12V current profile in Figure 1. (for 4TB models)
[4]
This condition occurs after OOB and Speed Negotiation completes but before the drive has received the Notify Spinup primitive.
[5]
See paragraph 6.3.1, "Conducted noise immunity." Specified voltage tolerance includes ripple, noise, and transient response.
[6]
During idle, the drive heads are relocated every 60 seconds to a random location within the band from three-quarters to maximum track.
Table 3
6TB drive DC power requirements
Notes
12.0Gb mode
(Amps)
(Amps)
(Watts)
Voltage
+5V
+12V [2]
Regulation
[5]
± 5% [2]
Avg idle current DCX
[1] [6]
0.40
0.55
8.57
Advanced idle current
Idle A
0.39
0.55
8.47
Idle B
0.32
0.48
7.28
Idle C
0.33
0.38
6.21
Standby
0.31
0.01
1.60
Maximum starting current
(peak DC) DC
[3]
0.78
2.05
28.45
(peak AC) AC
[3]
1.18
2.94
Delayed motor start (max) DC
0.34
0.02
Operating current (random read 4K16Q)
Typical DCX
[1]
0.43
0.84
12.28
Maximum DC
0.44
0.85
Maximum (peak) DC
1.02
2.49
Operating current (random write 4K16Q)
Typical DCX
[1]
0.47
0.61
9.61
Maximum DC
0.47
0.61
Maximum (peak) DC
0.78
2.44
Operating current (sequential read 64K16Q)
Typical DCX
[1]
0.77
0.59
10.95
Maximum DC
0.79
0.60
Maximum (peak) DC
1.05
1.06
Operating current (sequential write 64K16Q)
Typical DCX
[1]
0.65
0.62
10.66
Maximum DC
0.66
0.62
Maximum (peak) DC
0.80
1.82
