Physical/Electrical Specifications; Ac Power Requirements; Dc Power Requirements - Seagate ST11200N Product Manual

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7.0

Physical/electrical specifications

7.1 AC power requirements: None
7.2

DC Power requirements

The voltage and current requirements for a single drive are shown in the following table. Values indicated
apply at the drive power connector.
Voltage
Regulation [5]
Maximum Operating Current [1]
Average Idle Current [1] [3]
Maximum Starting Current (Peak)
Delayed Motor Start (Max) [4]
Peak Operating Current [6]
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[1] Measured with average reading DC ammeter. Instantaneous +12 V current peaks will exceed these
values.
[2] A -10% tolerance is permissible during power up. 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 +12 V current profile level T6 in Figure 7.2.2-1.
[4] This condition occurs when the Motor Start Option is enabled and the drive has not yet received a Start
Motor command.
[5] See paragraph 7.2.1 "Conducted Noise Immunity".
[6] Instantaneous peaks less than 5 msec. in duration are allowed.
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General Notes from Table 7.2-1:
1. At powerup, the motor current regulator limits the 12 volt current to a peak value of less than 2.0
amperes, although instantaneous peaks may exceed this value. These peaks should measure 5 msec.
duration or less.
2. Operating condition is defined as Random Seek Reads of 64 blocks.
3. Minimum current loading for each supply voltage is not less than 30% of the maximum operating current
shown.
4. The +5 and +12 volt supplies shall employ separate ground returns.
5. Where power is provided to multiple drives from a common supply, careful consideration for individual
drive power requirements should be noted. Where multiple units are powered on simultaneously, the
peak starting current must be available to each device.
Product Manual - Hawk 1 Family SCSI-2 (Volume 1), Rev. D
Table 7.2-1. DC power requirements
Single Ended
+5 V
+5%
0.88 A
0.48 A
0.88 A
0.68 A
Typ. [1] 0.72 A
Max. [1] 0.88 A
Max. (Peak) -
Differential
+12 V +5 V
+5%[2] +5%
1.0 A 1.08 A
0.55 A 0.63 A
2.0 A 0.98 A
0.7 A 0.68 A
0.60 A 0.7 A
1.0 A 1.08 A
2.0 A -
+12 V
+5%[2]
1.0 A
0.55 A
2.0 A
0.7 A
0.60 A
1.0 A
2.0 A