Seagate Cheetah 36XL ST318405LC, Product Manual, Page: 38 / 96

28 Cheetah 36XL Product Manual, Rev. E
6.3 Power dissipation
ST336705
For drives using single-ended interface circuits, typical power dissipation under idle conditions is 9.6 watts
(32.8 BTUs per hour).
For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is 9.6
watts (32.8 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see
Figures 9). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the correspond-
ing +5 volt current, +12 volt current, and total watts on the vertical axis. To calculate BTUs per hour, multiply
watts by 3.4123.
Figure 9. ST336705 DC current and power vs. input/output operations per second
4 11 16 6 33 45 24
I/Os per Second
Amperes
82 121 151
0.0
0.2
0.4
0.6
Watts
2
0
4
6
10
8
12
16
14
0.8
1.2
1.0
5V A
12V A
Watts