Seagate CHEETAH ST373207LW/LC - Manual (Page 42)

32 Cheetah 10K.7 SCSI Product Manual, Rev. D
ST3146707
For drives using single-ended interface circuits, typical power dissipation under idle conditions is 7.74 watts
(26.41 BTUs per hour).
For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is 7.74
watts (26.41 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see
Figures 8 and 9). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the cor-
responding +5 volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour,
multiply watts by 3.4123.
Figure 10. ST3146707 DC current and power vs. input/output operations per second (SE)
Figure 11. ST3146707 DC current and power vs. input/output operations per second (LVD)
ST3146707LC DC CURRENT/POWER vs THROUGHPUT (SE) Random 8 Block Reads
0.000
0.200
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
I/Os per Second
Am
pe
re
s
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Po
w
e
r (w
atts)
5Vo lt A
12 Vo lt A
Watts
ST3146707LC DC CURRENT/POWER vs THROUGHPUT (LVD) Random 8 Block Reads
0.000
0.200
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
I/Os per Second
Am
pe
re
s
0.00
2.00
4.00
6.00
8.00
10.00
12.00
14.00
16.00
18.00
Po
wer
(watts)
5Vo lt A
12 Vo lt A
Watts