Seagate Cheetah ST3146854, User Manual

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32 Cheetah 15K.4 SCSI Product Manual, Rev. D
ST373454
For drives using single-ended interface circuits, typical power dissipation under idle conditions is 9.52 watts
(32.49 BTUs per hour). For drives using low voltage differential interface circuits, typical power dissipation
under idle conditions is
9.47 watts (32.31 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see
Figures 10 and 11). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the
corresp5 volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour,
multiply watts by 3.4123.
Figure 10. ST373454 DC current and power vs. IOPS (SE)
Figure 11. ST373454 DC current and power vs. IOPS (LVD)
ST373454LC DC CURRENT/POWER vs THROUGHPUT (Single Ended)
Random 8 Block Reads
0.400
0.600
0.800
1.000
1.200
1.400
1.600
1.800
0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0
I/Os per Second
Am
p
e
re
s
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Pow
e
r (w
atts)
5Vo lt A
12 Vo lt A
Watts
ST373454LC DC CURRENT/POWER vs THROUGHPUT (Low Voltage Differential)
Random 8 Block Reads
0.400
0.600
0.800
1.000
1.200
1.400
1.600
1.800
0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0
I/Os per Second
Am
p
e
re
s
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Pow
e
r (w
atts)
5Vo lt A
12 Vo lt A
Watts