Specifications

26 Cheetah 15K.4 SAS Product Manual, Rev. B
[1] Measured with average reading DC ammeter. Instantaneous +12V current peaks will exceed these val-
ues. 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
14,904 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 2.
Table 3: ST373454SS DC power requirements
Notes
ST373454SS
3 Gbit mode
ST373454SS
1.5 Gbit mode
(Amps) (Amps) (Amps) (Amps)
Voltage +5V +12V [2] +5V +12V [2]
Regulation [5] ±5% ±5% [2] ±5% ±5% [2]
Avg idle current DCX [1] [7] 1.02 0.56 1.07 0.56
Maximum starting current
(peak DC) DC 3σ [3] 1.20 1.76 1.21 1.78
(peak AC) AC 3σ [3] 1.62 3.79 1.56 3.87
Delayed motor start (max) DC 3σ [1] [4] 1.03 0.04 0.91 0.04
Peak operating current:
Typical DCX [1] [6] 1.12 0.95 1.00 0.94
Maximum DC 3σ [1] 1.13 0.96 1.02 0.96
Maximum (peak) DC 3s 1.64 2.70 1.52 2.74
Table 4: ST336754SSDC power requirements
Notes
ST336754SS
3 Gbit mode
ST336754SS
1.5 Gbit mode
(Amps) (Amps) (Amps) (Amps)
Voltage +5V +12V [2] +5V +12V [2]
Regulation [5] ±5% ±5% [2] ±5% ±5% [2]
Avg idle current DCX [1] [7] 1.01 0.44 1.07 0.44
Maximum starting current
(peak DC) DC 3σ [3] 1.17 1.58 1.20 1.59
(peak AC) AC 3σ [3] 1.65 3.43 1.52 3.39
Delayed motor start (max) DC 3σ [1] [4] 1.02 0.04 0.91 0.04
Peak operating current:
Typical DCX [1] [6] 1.12 0.83 1.01 0.83
Maximum DC 3σ [1] 1.14 0.85 1.02 0.85
Maximum (peak) DC 3s 1.64 2.56 1.52 2.58