Seagate Barracuda ST11950N, Руководство по эксплуатации продукта

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Barracuda 1 and 2 Product Manual, Rev. C 33
[7] Operating condition is defined as a third-stroke seek at OD and read one
track. A command is issued every 0.07 sec.
[8] No terminator power. See Section 11.7.3.4.
[9] Idle is defined as track following at OD.
[10] Seeking is defined as a third-stroke seek at OD. A command is issued
every 20 msec.
[11] Read track is defined as repeat reads of track 15 with a 91% duty cycle.
[12] Read track is defined as repeat reads of track 15 with a 75% duty cycle.
Notes:
1. Minimum current loading for each supply voltage is not less than 7%
of the maximum operating current shown.
2. The
+
5V and
+
12V supplies use separate ground returns.
3. Where power is provided to multiple drives from a common supply,
careful consideration for individual drive power requirements should
be noted. Where multiple units are powered on simultaneously, the
peak starting current must be available to each device.
7.2.1 Conducted noise immunity
Noise is specified as a periodic and random distribution of frequencies
covering a band from DC to 10 MHz. Maximum allowed noise values given
below are peak-to-peak measurements and apply at the drive’s power
connector.
1 to 100 kHZ 100 kHz to 10 MHz
+++++
5V 150 mV 100 mV
+++++
12V 150 mV 100 mV
7.2.2 Power sequencing
The drive does not require power sequencing. The drive protects against
inadvertent writing during power-up and down. Daisy-chain operation re-
quires that power be maintained on the terminated device to ensure proper
termination of the peripheral I/O cables.
To automatically delay motor start based on the target ID (SCSI ID), select
the Delay Motor Start option and deselect the Enable Motor Start option. See
Section 10.1 for pin selection information.
To delay the motor until the drive receives a Start Unit command, select the
Enable Motor Start option.