6.3.3
Power supply generated ripple at drive power connector
+5V DC
+12V DC
Table 15 Power supply generated ripple at drive power connector
During drive start up and seeking 12-volt ripple is generated by the drive (referred to as dynamic loading). If the
power of several drives is daisy chained together, the power supply ripple plus the dynamic loading of the other
drives must remain within the above regulation tolerance. A common supply with separate power leads to each
drive is a more desirable method of power distribution.
To prevent external electrical noise from interfering with the performance of the drive, the drive must be held by
four screws in a user system frame which has no electrical level difference at the four screws position and has
less than ±300 millivolts peak to peak level difference to the ground of the drive power connector.
Maximum (mV pp)
200
250
Hitachi hard disk drive specifications
32
MHz
0-10
0-10