Seagate ST15150DC, Product Manual

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ST15150N/ND/W/WD/WC/DC Product Manual, Rev. D 35
7.2.3 12V current profile
Figure 14 identifies the drive’s
+
12V current profile. The current during the
various times is as shown.
Figure 14. Typical Barracuda 4 drive
+++++
12V current profile
T0 Power is applied to the drive.
T1 Controller self-tests are performed.
T2 Spindle begins to accelerate under current limiting after performing
internal diagnostics. See Note 1 of Table 1.
T3 The spindle is up to speed and the head-arm restraint is unlocked.
T4 Heads move from the landing zone to the data area.
T5 The adaptive calibration sequence is performed.
T6 Thermal calibration.
T7 Calibration is complete and the drive is ready for reading and writing.
Note. All times and currents are typical. See Table 1 for maximum current
requirements.
0 5 10 15 20 25 30
0.0
0.5
1.0
1.5
2.0
2.5
3.0
2.85
Peak AC
Nominal (average) curve
T0
T1
T2
T3
T4
T5
Minimum AC
TIME (S)
+12V CURRENT (A)
T6
T7
1.9