Figure 8. Pcb Temperature Measurement Locations; Figure 9. Hda Case Temperature Measurement Location - Seagate ST34501FC Cheetah 4LP Product Manual

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PCB and HDA temperatures
Card Component
HDA
GAAJ OP Amp
GAAJ Servo Control
GAAJ Motor Control
GAAJ Transceiver
To obtain the maximum temperature for each of the reference components listed, add 20°C to the 1,000,000
hour MTBF case temperatures. The maximum allowable HDA case temperature is 60°C (see Figure 9). Oper-
ation of the drive at the maximum case temperature is intended for short time periods only. Continuous opera-
tion at the elevated temperatures will reduce product reliability. The maximum allowable HDA case
temperature to meet the 1,000,000 hour MTBF is 45°C.
The air-flow pattern with which the temperature guidelines above were generated is shown in Figure 7. Local
average air velocities were 0.92 m/sec (180 lfpm) and inlet air temperature to the drive was 25°C (77°F), plus a
5°C temperature rise in the test enclosure (30°C ambient local to the drive).
Figure 8. PCB temperature measurement locations
Figure 9. HDA case temperature measurement location
Reference
Figure 9
1
2
3
4
1
4
HDA Temp.
Check Point
Cheetah 4LP FC Product Manual, Rev. A
MTBF
1,000,000 hours at
30°C case temperature
(°C)
50
48
50
52
56
3
2