USER RESPONSIBLE FOR VERIFYING VERSION AND COMPLETENESS
OEM FUNCTIONAL SPECIFICATION ULTRASTAR XP (DFHC) SSA MODELS 1.12/2.25 GB -1.0" HIGH
2.2 Power Requirements by Model

2.2.1 C1x Models

The following voltage specifications apply at the drive power connector. There is no special power on/off
sequencing required. The extra power needed for Brick O n Sled models and the + 38V power option are
described in 2.2.4, “CxB Models” on page 33.
Input Voltage
+ 5 Volts Supply 5V (± 5% during run a nd spin-up)
+1 2 Volts Supply 12V (± 5% during run) (+ 5% / -7 % during spin-up)
The following current values are the combination measured values of SCSI models and SSA Cx4 model. The
differences between SCSI and SSA is + 5V currents. Because of different interface electronics and speed, SSA
electronics card requires more +5 V current than SCSI. Read/Write Base Line is 290m a higher. Idle
Average is 500 ma higher. (290ma and 500ma differences were found by measuring SSA Cx4 model). SSA
+5 V current numbers are derived from SCSI +5 V current numbers by adding 290ma an d 500ma accord-
ingly.
Population Population
Power Supply Current Notes Mean Stand. Dev.
+5VDC (power-up) Minimum voltage slew rate = 4.5 V/sec
+5VDC (idle avg) 1.23Amps 0.02 Amps
+5VDC (R/W baseline) 1.25Amps10.05 Amps
+5VDC (R/W pulse) Base-to-peak .36 Amps 0.06Amps
+12VDC (power-up) Minimum voltage slew rate = 7.4 V/sec
+12VDC (idle avg) 0.28Amps 0.02 Amps
+12VDC (seek avg) 1 op/sec 0.0027 Amps 0.002 Amps
+12VDC (seek peak) 1.20Amps20.02 Amps
+12VDC (spin-up) 3.0 secmax 1.5 Amps30.1Amps
Drive power
Avg idle power 9.51 Watts .35 Watts
Avg R/ W power 30 ops/sec 10.58 Watts .35 Watts
1See Figure 1 on page 18 for a plot of how the read/write baseline and read/write pulse sum together.
2The idle average and seek peekshould be added together to determine the total 12 volt peak current. SeeFigure 2
on page 19for a typical buildup ofthese currents. Refer to exampleso n the following page to seehow to combine
these values.
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