Western Digital WDE2170 - Manual (Page 21)

WD Enterprise WDE2170/WDE4360 Specifications
4079-001045 Rev. B RELEASED 04-08-97 13
2.4.3. Input Voltage Requirements
The input voltage requirements for the WDE2170 and WDE4360 are as follows:
+ 5V
±
5% and + 12V
±
5%
2.4.4. Ripple
Table 2-9. Voltage Ripple
+12 VDC +5 VDC
Maximum Start: 400 mV (peak-to-peak)
Run: 150 mV (peak-to-peak)
100 mV (peak-to-peak)
Frequency 0-20 MHz 0-20 MHz
2.4.5. Bring-Up Sequence
After power is applied, the following events occur as the drive becomes ready for use.
Note: Typical spindle start time appears in Table 2-1.
1. The microprocessor tests itself, the on-board memory, and components on the
printed circuit board assembly (PCBA).
2. The SCSI interface is enabled to accept the following commands: Inquiry, Request
Sense, Start/Stop Unit, Test Unit Ready. Refer to the Western Digital SCSI
Implementation Guide (document number 4096-001116) for additionally supported
SCSI commands and features.
3. Internal electronic component initialization and testing continues.
4. If the Auto Start option is enabled, the motor spins up.
5. The servo system calibrates itself.
6. Additional configuration information is read from an area on the disk that is
reserved for the drive’s internal use.
7. A self test is performed on the read/write path.
8. The drive is ready to read and write data.
If an error occurs during the bring-up sequence, sense data is available if the SCSI
interface is working; otherwise the LED, if installed, flashes.
If a reassign was in progress when the drive was turned off, the drive automatically
completes that operation during startup.