Seagate ST3500620SS, ST31000640SS General DC power requirement notes, Conducted noise immunity

[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	=	250 mV pp from 0 to 100 kHz to 20 MHz
+12V	=	800 mV pp from 100 Hz to 8 KHz
		450 mV pp from 8 KHz to 20 KHz
		250 mV pp from 20 KHz to 5 MHz

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 are shown below in figure 2.

Note: All times and currents are typical. See Table 2 for maximum current requirements.

Barracuda ES.2 SAS Product Manual, Rev. E 25