IBM IC35L040AVVN07-0 - 40GB IDE Deskstar 120GXP 7200RPM UATA-100..., Технические характеристики

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The terms “Typical” and “Max” are used throughout this specification with the following meanings:
Typical. The average of the drive population tested at nominal environmental and voltage con-
ditions.
Max. The maximum value measured on any one drive over the full range of the environmental
and voltage conditions. (See Section 6.4, “Environment” on page 45 and Section 6.5, “DC Power
Requirements” on page 47.
Seek time is measured from the start of the motion of the actuator to the start of a reliable read or write
operation. "Reliable read or write" implies that error correction/recovery is not used to correct arrival pro-
blems. The average seek time is measured as the weighted average of all possible seek combinations.
max.
Σ
(max. + 1 – n) (Tn
in
+ Tn
out
)
n=1
Weighted Average =
__________________________________________________
(max. + 1) (Tn
in
+ Tn
out
)
where:
max
= maximum seek length
n
= seek length (1 to max)
Tn
in
= inward measured seek time for an n-track seek
Tn
out
= outward measured seek time for an n-track seek
4.4.2.2 Full stroke seek (without command overhead, including settling)
36.5 33.5 Write (Quiet Seek mode)
35.5 32.5 Read (Quiet Seek mode)
19.3 16.3 Write (20 GB & 40 GB models)
18.7 15.7 Write (60 GB – 120 GB models)
18.3 15.7 Read (20 GB & 40 GB models)
17.7 14.7 Read (60 GB – 120 GB models)
Max (ms) Typical (ms) Function
Figure 6. Full stroke seek time
Full stroke seek is measured as the average of 1000 full stroke seeks with a random head switch from
both directions (inward and outward).
4.4.2.3 Head switch time (Head skew)
2.0 54 kTPI
1.5 56.7 kTPI
Head switch time - typical (ms)
Figure 7. Head switch time
Head switch time is defined as the amount of time required by the fixed disk to complete a seek of the
next sequential track after reading the last sector in the current track
The measuring method is given in 4.4.5 “Throughput” on page 17.
Deskstar 120GXP hard disk drive specifications
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