18 Barracuda 9 Installation Guide, Rev. B
2
A –10% tolerance is permissible during initial start of the spin-
dle 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 9 Product Man-
ual
(publication number 83329030).
4
This condition occurs when the Motor Start option is enabled
and the drive has not yet received a Start Motor command.
5
See “Conducted noise immunity” in the
Barracuda 9 Product
Manual.
The specified voltage tolerance is inclusive of ripple,
noise, and transient response.
6
At power-up, the motor current regulator limits the +12V cur-
rent to an average value of less than 1.4A, although instanta-
neous 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.
8
Use separate ground returns for +5V and +12V supplies.
9
Where power is provided to multiple drives from a common
supply, carefully consider individual-drive power requirements.
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. A command is issued every 0.075 seconds (every 0.063
seconds on wide and SCA drives).