Hitachi IC25N020ATMR04, Specifications

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Travelstar 80GN Hard Disk Drive Specification
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4.4 Performance characteristics
Drive performance is characterized by the following parameters:
• Command overhead
• Mechanical head positioning
- Seek time
- Latency
• Data transfer speed
• Buffering operation (read ahead/write cache)
Note: All the above parameters contribute to drive performance. There are other parameters that contribute to the
performance of the actual system. This specification tries to define the bare drive characteristics, not system
throughput, which depends on the system and the application.
The following table gives a typical value for each parameter. The detailed descriptions are found in Section 5.0,
“Data integrity” beginning on page 21.
4.4.1 Command overhead
Command overhead time is defined as the interval from the time that a drive receives a command to the time that
the actuator starts its motion
4.4.2 Mechanical positioning
4.4.2.1 Average seek time (including settling)
Table 4: Performance characteristics
Function
Average random seek time - read (ms) 12
Average random seek time - write (ms) 14
Rotational speed (RPM) 4200
Power-on-to-ready (sec) 3.0
Command overhead (ms) 1.0
Disk-buffer data transfer (Mb/s) 350
Buffer-host data transfer (Mb/s) 100
Table 5: Mechanical positioning performance
Command type Typical (ms) Max (ms)
Read 12 16
Write 14 17