26
Pulsar XT.2 SAS Product Manual, Rev. B
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 start, are measured after a 10-minute warm up.
7.3.1
Conducted noise immunity
Noise is specified as a periodic and random distribution of frequencies covering a defined frequency. Maximum
allowed noise values given below are peak-to-peak measurements and apply at the drive power connector.
7.3.2
Power sequencing
The drive does not require power sequencing. The drive protects against inadvertent writing during power-up
and down.
7.3.3
Current profiles
The +12V and +5V current profiles for the Pulsar 10K.4 drives are shown below.
Figure 1.
Current profiles for 400GB models
+5v
=
250 mV pp from 100 Hz to 20 MHz.
+12v
=
450 mV pp from 100 Hz to 100 KHz.
250 mV pp from 100 KHz to 20 MHz.
150 mV pp from 20 MHz to 80 MHz.
