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Cheetah 15K.5 FC Product Manual, Rev. F
ST3146855FC
Typical power dissipation under idle conditions in 4 Gbit operation is 10.56 watts (36.0 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following I/O rate curve (see Figure
7). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the corresponding +5
volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour, multiply watts by
3.4123.
Figure 8. ST3146855FC DC current and power vs. input/output operations per second at 4 Gbit
ST3146855FC CURRENT/POWER vs THROUGHPUT (FC - 4GB)
Random 8 Block Reads
0.000
0.200
0.400
0.600
0.800
1. 0 0 0
1. 2 0 0
1. 4 0 0
0.0 50.0 100.0 150.0 200.0 250.0 300.0 350.0 400.0
I/Os per Second
Amperes
0.00
2.00
4.00
6.00
8.00
10 . 0 0
12 . 0 0
14 . 0 0
16 . 0 0
Power (watts)
5Volt A
12 V o l t A
Watts