Seagate ST3300555SS manual General DC power requirement notes, Conducted noise immunity, +5V +12V

Models: ST3300555SS ST3146755SS ST373355SS

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Degrees C ambient.

[2]For +12 V, a –10% tolerance is allowed during initial spindle start but must return to ±5% before reaching 15,000 RPM. The ±5% must be maintained after the drive signifies that its power-up sequence has been completed and that the drive is able to accept selection by the host initiator.

[3]See +12V current profile in Figures 2, 3, and 4.

[4]This condition occurs after OOB and Speed Negotiation completes but before the drive has received the Notify Spinup primitive.

[5]See paragraph 6.2.1, "Conducted noise immunity." Specified voltage tolerance includes ripple, noise, and transient response.

[6]During idle, the drive heads are relocated every 60 seconds to a random location within the band from three-quarters to maximum track.

General DC power requirement notes.

1.Minimum current loading for each supply voltage is not less than 1.7% of the maximum operating current shown.

2.The +5V and +12V supplies should employ 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.

4.Parameters, other than spindle start, are measured after a 10-minute warm up.

5.No terminator power.

6.2.1Conducted 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 power connector.

 

+5V

+12V

0 to 100 kHz

150mV

150mV

100 kHz to 10 MHz

100mV

100mV

6.2.2Power sequencing

The drive does not require power sequencing. The drive protects against inadvertent writing during power-up and down.

6.2.3Current profiles

The +12V and +5V current profiles for these drive are shown below in the following figures.

Note: All times and currents are typical. See Tables 2, 3, and 4 for maximum current requirements.

Cheetah T10 SAS Product Manual, Rev. A

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Seagate ST3300555SS manual General DC power requirement notes, Conducted noise immunity, Power sequencing, Current profiles