Hitachi HTS543280L9SA00 manual 4.4.2Mechanical positioning, Average seek time including settling

Models: HTS543225L9A300 HTS543232L9A300 HTS543216L9A300 HTS543216L9SA00 HTS543212L9A300 HTS543280L9SA00

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4.4.2Mechanical positioning
Typical Max.

5K320 SATA OEM Specification

4.4.2Mechanical positioning

4.4.2.1 Average seek time (including settling)

Command Type

Typical (ms)

Read

12

Write

13

Table 5. Mechanical positioning performance

Max. (ms)

14

15

Typical and Max. are defined throughout the performance specification as follows:

Average of the drive population tested at nominal environmental and voltage conditions. Maximum value measured on any one drive over the full range of the environmental and voltage conditions. (See section 6.1, "Environment" and section 6.2, "DC power requirements" )

The seek time is measured from the start of motion of the actuator to the start of a reliable read or write operation. A reliable read or write operation implies that error correction/recovery is not employed to correct arrival problems. The Average Seek Time is measured as the weighted average of all possible seek combinations.

max.

Σ (max. + 1 – n)(Tnin + Tnout)

n=1

Weighted Average = ––––––––––––––––––––––––––––

(max. + 1)(max)

Where: max. = maximum seek length n = seek length (1-to-max.)

Tnin

= inward measured seek time for an n-track seek

Tnout

= outward measured seek time for an n-track seek

4.4.2.2Full stroke seek

Command Type

Typical (ms)

Max. (ms)

Read

20.0

25.0

Write

21.0

26.0

Table 6. Full stroke seek time

Full stroke seek time in milliseconds is the average time of 1000 full stroke seeks.

4.4.2.3Single track seek time (without command overhead, including settling)

Command Type

Typical (ms)

Maximum (ms)

Read

1.0

2.0

Write

1.1

2.2

Table 7. Single track seek time

Single track seek is measured as the average of one (1) single track seek from every track in both directions (inward and outward).

4.4.2.4Average latency

Rotational Speed

Time for one revolution

Average Latency

(RPM)

(ms)

(ms)

5400

11.1

5.5

Table 8. Latency time

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Hitachi HTS543280L9SA00 manual 4.4.2Mechanical positioning, Average seek time including settling, 4.4.2.2Full stroke seek