Ripple Voltage; Table 24. Model 73Gb; Table 25. Model 36Gb; Table 26. Power Supply Generated Ripple At Drive Power Connector - Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications

Table 24: Model 73GB
Model 73GB
IO/Sec
Start Peak DC
Start Peak AC
Idle
Idle Ripple
Random Peak AC 215
Random W/R(DC) 215
IOPS 150
120
90
60
30
Table 25: Model 36GB
Model 36GB
IO/Sec
Start Peak DC
Start Peak AC
Idle
Idle Ripple
Random Peak AC 220
Random W/R(DC) 220
IOPS 150
120
90
60
30

9.2 Ripple voltage

Table 26: Power supply generated ripple at drive power connector
+5 V DC
+12 V DC
During drive start up and seek, 12 volt ripple is generated by the drive (referred to as dynamic loading). If the power of several
drives is daisy chained, the power supply ripple plus other drive dynamic loading must remain within the regulation tolerance
of +5%. A common supply with separate power leads to each drive is a more desirable method of power distribution.
To prevent external electrical noise from interfering with the drive's performance, the drive must be held by four screws in a
user system frame that has no electrical level difference at the four screw positions. The drive enclosure must not be used in
the current return path of the drive power supply. The maximum common-mode noise current passing through the drive must
Current Current Total Average
+5V +12V Power (W)
0.70 1.70 ---
0.80 2.30
0.55 0.51 8.83
0.29 0.41 ---
1.51 2.17 ---
0.70 .87 13.88
0.67 0.78 12.85
0.65 0.73 12.04
0.62 0.67 11.24
0.60 0.62 10.44
0.57 0.56 9.63
Current Current Total Average
+5V +12V Power (W)
0.70 1.70 ---
0.80 2.30
0.55 0.45 8.19
0.27 0.37 ---
1.41 2.15 ---
0.70 0.80 13.15
0.67 0.65 11.81
0.64 0.65 11.08
0.62 0.60 10.36
0.60 0.55 9.63
0.57 0.50 8.90
Maximum (mV pp)
250
250
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
Note
Maximum
Peak
Avg
Pk to Pk
Peak 2KB Qd = 4
Avg, 2KB Qd = 4
Avg, 2KB, Qd=1
Note
Maximum
Peak
Avg
Pk to Pk
Peak 2KB Qd = 4
Avg, 2KB Qd = 4
Avg, 2KB, Qd=1
MHz
0-10
0-10
38