Fujitsu MAW3073NC, Product/Maintenance Manual

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4-8 C141-E226
4.2 Power Supply Requirements
(1) Allowable input voltage and current
The power supply input voltage measured at the power supply connector pin of the HDD
(receiving end) must satisfy the requirement given in Subsection 2.1.3. (For other requirements,
see Items (4) and (5) below.)
(2) Current waveform (reference)
Figure 4.8 shows the spin-up current waveform of +12V DC.
Time (2 sec/div)
Time (2 sec/div) Time (2 sec/div)
MAW3300NC/NP
MAW3147NC/NP
MAW3073NC/NP
Cu
rr
en
t (5
0
0
mA/d
iv
)
C
u
rr
e
nt
(
5
00m
A
/d
iv)
Cu
rr
en
t (5
0
0
mA/d
iv
)
Figure 4.8 Spin-up current waveform (+12V DC)
(3)
Power on/off sequence
a) The order of the power on/off sequence of +5V DC and +12V DC, supplied to the HDD, does
not matter.
b) In a system which uses the terminating resistor power supply signal (TERMPWR) on the SCSI
bus, the requirements for +5V DC given in Figure 4.9 must be satisfied between the HDD and
at least one of the SCSI devices supplying power to that signal.
Figure 4.9 Power on/off sequence (1)