User manual

Hitachi hard disk drive specifications
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6.4 Reliability
6.4.1 Data integrity
No more than one sector is lost at Power loss condition during the write operation when the write cache option is
disabled. If the write cache option is active, the data in write cache will be lost. To prevent the loss of customer
data, it is recommended that the last write access before power off be issued after setting the write cache off.
6.4.2 Cable noise interference
To avoid any degradation of performance throughput or error rate when the interface cable is routed on top or
comes in contact with the HDA assembly, the drive must be grounded electrically to the system frame by four
screws. The common mode noise or voltage level difference between the system frame and power cable ground
or AT interface cable ground should be in the allowable level specified in the power requirement section.
6.4.3 Load/Unload
The product supports a minimum of 300,000 normal load/unloads in a 40° C environment.
Load/unload is invoked by transition of the HDD's power mode.
Idle <-> unload idle
Idle <-> Low rpm idle*
*Note: Low rpm idle mode is supported on specific drive PN, only.
6.4.4 Start/stop cycles
The drive withstands a minimum of 50,000 start/stop cycles in a 40° C environment and a minimum of 10,000
start/stop cycles in extreme temperature or humidity within the operating range. .
6.4.5 Preventive maintenance
None
6.4.6 Data reliability
Probability of not recovering data is 1 in 10
14
bits read for Deskstar/CinemaStar models, 1 in 10
15
bits read for
Ultrastar model.
ECC On The Fly correction
 1 Symbol : 10 bits
 No Interleave
 34 symbol ECC
 This implementation always recovers 16 random errors and a 310-bit continuous burst error