Seagate Barracuda 18XL ST318416N, Product Manual

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Barracuda 18XL Product Manual, Rev. A 21
6.0 Physical/electrical specifications
This section provides information relating to the physical and electrical characteristics of the Barracuda 18XL
drive.
6.1 AC power requirements
None.
6.2 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. The single ended power requirements includes the internal disc drive SCSI I/O ter-
mination. The table shows current values in Amperes. See also Figure 3c for current values vs. number of I/O
operations.
Table 2: DC power requirements
Notes.
[1] Measured with average reading DC ammeter. Instant12 V current peaks will exceed these val-
ues. Power supply is at nominal voltages.
[2] For +12 V, a –10% droop is permissible during initial start of spindle, and must return to ±5% before 7,200
rpm is reached. 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 in Figure 3a.
[4] This condition occurs when the Motor Start Option is enabled and the drive has not yet received a Start
Motor command.
18.373 GB drives Notes
ST318436 ST318426 ST318416
LW/LC–LVD LWV/LCV–LVD LW/LC–LVD N/W–SE
Voltage +5 V +12 V +5 V +12 V +5 V +12 V +5 V +12 V
Regulation [5][2] ±5% ±5% ±5% ±5% ±5% ±5% ±5% ±5%
Average idle current DCX [1] 0.80 0.30 0.80 0.30 0.80 0.30 0.80 0.30
Maximum starting current
(peak DC)
(peak AC) [3]
[3] 1.0 2.4
2.7 1.0 2.4
2.7 1.0 2.4
2.7 1.0 2.4
2.7
Delayed motor start (max) DC [1][4] 0.70 0.05 0.70 0.05 0.70 0.05 0.70 0.05
Peak operating current
Typical DCX
Maximum DC
Maximum (Peak) [1][6]
[1] 0.90
1.10
1.60 0.60
0.70
2.50 0.90
1.10
1.60 0.60
0.70
2.50 0.90
1.10
1.60 0.60
0.70
2.50 0.90
1.10
1.60 0.60
0.70
2.50
9.186 GB drives Notes
ST39236 ST39226 ST39216
LW/LC–LVD LWV/LCV–LVD LW/LC–LVD N/W–SE
Voltage +5 V +12 V +5 V +12 V +5 V +12 V +5 V +12 V
Regulation [5][2] ±5% ±5% ±5% ±5% ±5% ±5% ±5% ±5%
Average idle current DCX [1] 0.80 0.25 0.80 0.25 0.80 0.25 0.80 0.25
Maximum starting current
(peak DC)
(peak AC) [3]
[3] 1.0 1.7
2.4 1.0 1.7
2.4 1.0 1.7
2.4 1.0 1.7
2.4
Delayed motor start (max) DC [1][4] 0.70 0.05 0.70 0.05 0.70 0.05 0.70 0.05
Peak operating current
Typical DCX
Maximum DC
Maximum (Peak) [1][6]
[1] 0.90
1.00
1.40 0.50
0.80
2.30 0.90
1.00
1.40 0.50
0.80
2.30 0.90
1.00
1.40 0.50
0.80
2.30 0.90
1.00
1.40 0.50
0.80
2.30