Product Manual - Hawk 2LP Family (Wide) SCSI-2 (Volume 1), Rev. A
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7.2.2
Power sequencing
The drive does not require power sequencing. The drive protects against inadvertent writing during power up
and down. Daisy-chain operation requires that power be maintained on the terminated drive to ensure proper
termination of the peripheral I/O cables. For the benefit of the system power supply, drive power up can be
delayed using the motor start delay option. See Section 10.1.
7.2.3
12 V - current profile
Figure 7.2.2-1 identifies the drive +5 V and +12 V current profile. The current during the various times is as
shown:
T -Power is applied to the drive.
T1 -Controller self tests are performed.
T2 -Spindle begins to accelerate under current limiting after performing drive internal diagnostics. See Note
1 of Table 7.2-1.
T3 -The spindle is up to speed and the Head-Arm restraint is unlocked.
T4 -The heads move from the landing zone to the data area.
T5 -The adaptive calibration sequence is performed.
T6 -Calibration is complete and the drive is ready for reading and writing.
Note.
All times and currents are typical. See Table 7.2-1 for maximum current
requirements.
Figure 7.2.2-1. Typical Hawk 2LP family (Wide) drive +5 V and +12 V current profile
16
20
0
2
4
6
8
10
Seconds
Seconds
12
14
16
18
0.2
0.4
0.6
5V
Current
(amps)
0.8
20
T1
T
T2
T3
0
2
4
6
8
10
12
14
18
0.5
1.0
1.5
12V
Current
(amps)
2.0
2.5
T6
T4
T5
