Seagate ST373455LC - Cheetah 73.4 GB Hard Drive Installation Manual page 19

Barracuda 18LP Installation Guide, Rev. B
Table 2. DC power requirements (Amps), multimode
(SE/LVD)
Voltage
Regulation [5]
Avg. idle current
DCX [1]
Max. starting current
(peak DC) [3]
(peak AC) [3]
Delayed motor
start (max) [1][4]
Peak operating current
Typical DCX [1] [6]
Maximum DC [1]
Maximum (peak)
[1] Measured with an average reading DC ammeter. Instanta-
neous +12V current peaks will exceed these values.
[2] A –10% droop is permissible during initial start of the spindle
but must return to ±5% before reaching 7,200 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 the +12V current profile in the Barracuda 18LP Product
Manual (publication number 77767526).
[4] This condition occurs when the Motor Start option is enabled
and the drive has not yet received a Start Motor command.
ST39175LW/LC
+5V +12V
±5% ±5%[2]
0.75 0.35
1.0 1.3
— 2.4
0.65 0.05
1.0 0.7
1.3 1.4
1.7 2.1
ST318275LW/LC
+5V +12V
±5% ±5%[2]
0.75 0.5
1.05 1.6
— 2.4
0.65 0.05
1.05 0.8
1.4 1.5
1.7 2.4
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