Seagate Cheetah 15K.5 FC ST373455FC - Manual (Page 34)

24 Cheetah 15K.5 FC Product Manual, Rev. D
[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
15000 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 when the Motor Start option is enabled and the drive has not yet received a Start
Motor command.
[5] See paragraph 6.2.1, "Conducted noise immunity." Specified voltage tolerance includes ripple, noise, and
transient response.
[6] Operating condition is defined as random 8 block reads at 309 s I/Os per second for ST3300655FC and
Table 3: DC power requirements for ST3146855FC model
1 Gbit 2 Gbit 4 Gbit
Notes (Amps) (Amps) (Amps) (Amps) (Amps) (Amps)
Voltage +5V +12V [2] +5V +12V [2] +5V +12V [2]
Regulation [5] ±5% ±5% [2] ±5% ±5% [2] ±5% ±5% [2]
Avg idle current DCX [1] [7] 0.77 0.54 0.79 0.53 0.84 0.53
Maximum starting current
(peak DC) DC 3
σ
[3] 0.78 2.08 0.80 2.08 0.86 2.08
(peak AC) AC 3
σ
[3] 1.18 3.70 1.17 3.70 1.27 3.65
Delayed motor start (max) DC 3
σ
[1] [4] 0.44 0.03 0.47 0.03 0.52 0.03
Peak operating current:
Typical DCX [1] [6] 0.62 0.89 0.76 0.88 0.52 0.87
Maximum DC 3 σ [1] 0.75 0.93 0.77 0.94 0.80 0.93
Maximum (peak) DC 3 σ 1.54 2.68 1.54 2.70 1.60 2.62
Table 4: DC power requirements for ST373455FC model
1 Gbit 2 Gbit 4 Gbit
Notes (Amps) (Amps) (Amps) (Amps) (Amps) (Amps)
Voltage +5V +12V [2] +5V +12V [2] +5V +12V [2]
Regulation [5] ±5% ±5% [2] ±5% ±5% [2] ±5% ±5% [2]
Avg idle current DCX [1] [7] 0.76 0.41 0.83 0.42 0.84 0.41
Maximum starting current
(peak DC) DC 3 σ [3] 0.77 2.02 0.80 2.02 0.84 2.02
(peak AC) AC 3 σ [3] 1.10 3.51 1.17 3.57 1.29 3.48
Delayed motor start (max) DC 3 σ [1] [4] 0.45 0.03 0.49 0.03 0.53 0.03
Peak operating current:
Typical DCX [1] [6] 0.69 0.73 0.74 0.74 0.78 0.76
Maximum DC 3 σ [1] 0.71 0.79 0.77 0.79 0.81 0.80
Maximum (peak) DC 3 σ 1.42 2.46 1.54 2.48 1.56 2.50