Fujitsu MAW3300fc 用户手册

 

4-8 

C141-E235 

(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) 
below.) 

(2) 

Current waveform (reference) 

 

Figure 4.7 shows the waveform of +12 VDC. 

MAW3300FC 

Cu

rr

ent (

5

0

0

mA/div) 

Time (2 sec/div) 

MAW3147FC 

C

u

rr

en

t (500mA

/div)

 

Time (2 sec/div)

MAW3073FC 

C

u

rr

en

t (500mA

/div)

 

Time (2 sec/div)

 

 
(3) 

Power on/off sequence 

 

The order of the power on/off sequence of +5 VDC and +12 VDC, supplied to the HDD, does not 
matter. 

 
(4) 

Sequential starting of spindle motors 

 

After power is turned on to the HDD, a large amount of current flows in the +12 VDC line when the 
spindle motor rotation starts.  Therefore, if more than one HDD is used, the spindle motors should be 
started sequentially using one of the following procedures to prevent overload of the power supply 
unit. 

a)  Issue START/STOP commands at more than 12-second intervals to start the spindle motors.  For 

details of this command specification, refer to Fibre Channel Interface Specifications. 

 

b)  Turn on the +12 VDC power in the power supply unit at 12-second intervals or more to start the 

spindle motors sequentially.