Seagate ST31250W/WD/WC/DC User Manual
Barracuda 2LP Installation Guide, Rev. E
17
1
Measured with an average reading DC ammeter. Instanta-
neous +12V current peaks will exceed these values.
neous +12V current peaks will exceed these values.
2
A
−
10% tolerance 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.
is able to accept selection by the host initiator.
3
See the
+
12V current profile in the
Barracuda 2LP Product
Manual (publication number 83328930).
4
This condition occurs when the Motor Start option is enabled
and the drive has not yet received a Start Motor command.
and the drive has not yet received a Start Motor command.
5
See “Conducted noise immunity” in the
Barracuda 2LP
Product Manual. The specified voltage tolerance is inclusive
of ripple, noise, and transient response.
of ripple, noise, and transient response.
6
At power-up, the motor current regulator limits the
+
12V
current to an average value of less than 1.4A, although
instantaneous peaks may exceed this value. These peaks
should measure 5 msec duration or less.
instantaneous peaks may exceed this value. These peaks
should measure 5 msec duration or less.
7
Minimum current loading for each supply voltage is not less
than 4% of the maximum operating current shown.
than 4% of the maximum operating current shown.
8
Use separate ground returns for
+
5 and
+
12V supplies.
9
Where power is provided to multiple drives from a common
supply, carefully consider individual-drive power require-
ments. Where multiple units are powered on simultaneously,
be sure the peak starting current is available to each device.
supply, carefully consider individual-drive power require-
ments. Where multiple units are powered on simultaneously,
be sure the peak starting current is available to each device.
10
Operating condition is a third-stroke seek at OD and read
one Track. The command is issued every 0.075 seconds
(every 0.063 seconds on wide and SCA drives).
one Track. The command is issued every 0.075 seconds
(every 0.063 seconds on wide and SCA drives).