Seagate ST373405LW Product Manual - Page 35

Cheetah 73LP Product Manual, Rev. C, Power dissipation

Page 35 highlights

Cheetah 73LP Product Manual, Rev. C 25 6.3 Power dissipation ST373405 For drives using single-ended interface circuits, typical power dissipation under idle conditions is 9.9 watts (33.8 BTUs per hour). For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is 10.2 watts (34.8 BTUs per hour). To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see Figures 7 and 8). 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. 1.800 1.600 1.400 1.200 17 Amperes 1.000 15 0.800 13 0.600 11 Figure 7. 0.400 0 50 100 150 200 250 I/Os per Second ST373405 DC current and power vs. input/output operations per second (SE) 5V A 12V A Watts Watts 1.800 1.600 1.400 1.200 17 Amperes 1.000 15 0.800 13 0.600 11 Figure 8. 0.400 0 50 100 150 200 250 I/Os per Second ST373405 DC current and power vs. input/output operations per second (LVD) 5V A 12V A Watts Watts

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Cheetah 73LP Product Manual, Rev. C
25
6.3
Power dissipation
ST373405
For drives using single-ended interface circuits, typical power dissipation under idle conditions is 9.9 watts
(33.8 BTUs per hour).
For drives using low voltage differential interface circuits, typical power dissipation under idle conditions is 10.2
watts (34.8 BTUs per hour).
To obtain operating power for typical random read operations, refer to the following two I/O rate curves (see
Figures 7 and 8). 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 7.
ST373405 DC current and power vs. input/output operations per second (SE)
Figure 8.
ST373405 DC current and power vs. input/output operations per second (LVD)
1.800
0
50
100
I/Os per Second
Amperes
200
250
0.400
0.600
0.800
1.000
11
Watts
13
15
17
1.200
1.600
1.400
150
5V A
12V A
Watts
1.800
0
50
100
I/Os per Second
Amperes
200
250
0.400
0.600
0.800
1.000
11
Watts
13
15
17
1.200
1.600
1.400
150
5V A
12V A
Watts