Dc Power Requirements; Table 20. Input Voltage - Hitachi HUS151473VL3800 - Ultrastar 73.4 GB Hard Drive Specifications

9.0 DC power requirements

The following voltage specification applies at the drive power connector. Connections to the drive should be made in a safety
extra low voltage (SELV) circuit. There is no power off sequencing requirement.
The power on sequencing requirement is as follows:
If 5V is turned on before 12V, then the sequence delay must be less than 2 seconds.
If 12V is turned on before 5V, there is no time limit.
Failure to power on sequence correctly will prevent motor spin up.
Adequate secondary over-current protection is the responsibility of the system. A 10 A limit is required for safety purposes.
Table 20: Input voltage
+5 Volts supply
+12 Volts supply
1.
-8% of 12V voltage margin is acceptable during spin-up, but the drive ready time as specified in section 4.5.2 is not guar-
anteed.
CAUTION: To avoid damage to the drive electronics, power supply voltage spikes must not exceed 5.5V.
Tolerance
+/- 5%
1
+/- 5%,
Hitachi Ultrastar 15K147 SCSI Hard Disk Drive Specification
Absolute max
spike voltage
5.5 V
15 V
35
Supply rise time
0-200 ms
0-400 ms