Seagate Barracuda ST11950N, Руководство по эксплуатации продукта

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32 Barracuda 1 and 2 Product Manual, Rev. C
Table 2. DC power requirements
for ST11950W/WD and ST12550W/WD drives
ST11950W & ST11950WD &
ST12550W ST12550WD
5V
[8]
12V 5V
[8]
12V
Voltage regulation
[5]
Notes ±5% ±5%
[2]
±5% ±5%
[2]
Amps
Max operating current DC 3
σ
[1] 1.04 0.95 1.3 0.95
Avg idle current
OD DC X [1] [9] 1.0 0.84 1.1 0.84
Max start current
(peak) DC 3
σ
[3] [6] 1.0 2.18 1.1 2.18
(peak) AC 3
σ
[3] – 3.1 – 3.1
Delay motor start (max)
DC 3
σ
[1] [4] 1.0 0.19 1.1 0.19
Peak operating current
Typical DC X [1] [7] 1.03 0.91 1.21 0.91
Maximum DC 3
σ
[1] 1.04 0.95 1.3 0.95
Maximum (peak) AC 3
σ
1.2 1.87 2.0 1.87
Track following at
OD DC X [1] 1.0 0.84 1.1 0.84
ID DC X [1] 1.0 0.9 1.1 0.9
Read track
OD DC 3
σ
[1] [12] 1.1 0.85 1.4 0.85
AC 3
σ
1.3 1.2 2.0 1.2
Seeking
Typical DC X [1] [10] 1.0 1.2 1.1 1.2
Maximum DC 3
σ
[1] 1.1 1.2 1.2 1.2
Maximum (peak) AC 3
σ
1.2 1.8 2.0 1.8
Notes:
[1] Measured with average reading DC ammeter. Instantaneous
+
12V
current peaks will exceed these values.
[2] A –10% tolerance is permissible during initial start of the spindle and
must return to
±
5% before reaching 7,200 RPM. The
±
5% must be
maintained after the drive signals that its power-up sequence has
been completed and that it can accept selection by the host initiator.
[3] See Figure 12.
[4] This condition occurs when the Motor Start Option is enabled and the
drive has not yet received a start motor command.
[5] See Section 7.2.1. Specified voltage tolerance includes ripple, noise,
and transient response.
[6] At power-up, the motor current regulator limits the 12V current to an
average value of less than 2.0A, although instantaneous peaks may
exceed this value. These peaks should measure 5 msec duration or less.