Seagate Cheetah 73 ST173404LC, Product Manual

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24 Cheetah 73 Product Manual, Rev. D
6.3 Power dissipation
For drives using single-ended interface circuits, typical power dissipation under idle conditions is 16.1 watts (55
BTUs per hour).
For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is
16.36 watts (55.8 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see fig-
ures 6 and 7). Locate the typical I/O rate for a drive in your system on the horizontal axis and read the corre-
sp5 volt current, +12 volts current, and total watts on the vertical axis. To caluclate BTUs per hour,
multiply watts by 3.4123.
Figure 6. DC current and power vs. input/output operations per second (single-ended mode)
Figure 7. DC current and power vs. input/output operations per second (LVD mode)
0.400
0 50 100
I/Os per Second
Amperes
150 200
0.600
0.800
1.000
1.200
16
18
Watts
20
22
1.400
1.800
1.600
5V A
12V A
Watts
0 50 100
I/Os per Second
Amperes
150 200
0.400
0.600
0.800
1.000
Watts
16
18
20
22
1.200
1.800
1.600
1.400
5V A
12V A
Watts