22
Cheetah 15K.7 SAS Product Manual, Rev. A
[1]
Measured with average reading DC ammeter or equivalent sampling scope. 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
15,000 RPM. The ±5% must be maintained after the drive signifies that its power-up sequence has been
completed and that the drive is able to accept selection by the host initiator.
[3]
See +12V current profile in Figure 1.
[4]
This condition occurs after OOB and Speed Negotiation completes but before the drive has received the
Notify Spinup primitive.
Table 15:
300 GB
DC power requirements
Notes
ST3300657SS
ST3300557SS
3 Gbit mode
ST3300657SS
ST3300557SS
6 Gbit mode
(Amps)
(Amps)
(Amps)
(Amps)
Voltage
+5V
+12V [2]
+5V
+12V [2]
Regulation
[5]
±5%
±5% [2]
±5%
±5% [2]
Avg idle current
[1] [7]
0.34
0.58
0.35
0.58
Maximum starting current
(peak DC) DC
3
σ
[3]
0.53
1.92
0.54
1.92
(peak AC) AC
3
σ
[3]
0.98
3.82
0.86
3.98
Delayed motor start (max) DC
3
σ
[1] [4]
0.47
0.04
0.48
0.04
Peak operating current (random read):
Typical DC
[1][6]
[1]
0.41
0.88
0.42
0.90
Maximum DC
3
σ
[1]
0.42
0.95
0.43
0.95
Maximum DC (peak)
3
σ
1.18
2.78
1.20
2.74
Peak operating current (random write):
Typical DC
[1][6]
[1]
0.48
0.80
0.49
0.81
Maximum DC
3
σ
[1]
0.49
0.83
0.51
0.82
Maximum DC (peak)
3
σ
1.18
2.68
1.20
2.66
Peak operating current (sequential read):
Typical DC
[1][6]
[1]
0.91
0.59
0.92
0.59
Maximum DC
3
σ
[1]
0.93
0.60
0.94
0.61
Maximum DC (peak)
3
σ
1.20
0.98
1.24
1.00
Peak operating current (sequential write):
Typical DC
[1][6]
[1]
0.89
0.58
0.90
0.59
Maximum DC
3
σ
[1]
0.93
0.60
0.94
0.60
Maximum DC (peak)
3
σ
1.22
0.98
1.22
0.96
