Typical Power-Up And Power-Down Sequence; Power-Up Sequence; Figure 1. Typical Startup Current Profile - Seagate Medalist 1640 Product Manual

8 Medalist 1640 and 2140 Product Manual, January 1996

1.7 Typical power-up and power-down sequence

A typical power-up and power-down sequence is described below to
assist you in evaluating the drive's performance. It is not a performance
specification.
Milliamps
1,600
1,400
1,200
1,000
800
600
400
200
0
1 101 201 301 401 501 601 701 801 901 1001
0 1.0

Figure 1. Typical startup current profile

1.7.1 Power-up sequence

1. Power is applied to the drive.
2. After a delay, the startup current is applied and the spindle begins to
turn.
3. The accelerating current is applied, causing the spindle speed to
increase.
4. The spindle speed is close to the final correct value. The drive begins
to lock in speed-control circuits.
5. The arm-lock mechanism releases the arm.
6. The final speed-control lock is achieved.
7. The heads are positioned over track 0, and the drive has completed
its power-up sequence.
2.0 3.0 4.0 5.0 6.0 7.0
Seconds
8.0 9.0 10.0