Fujitsu MAP3735FC, MAP3147FC manual Hardware Specifications, Error rate, Reliability

2.1 Hardware Specifications

(*1) For detail condition, see Section 4.1.

(*2) Vibration applied to the drive is measured at near the mounting screw hole on the frame as much as possible.

(*3) At random seek write/read and default on retry setting with log sweep vibration.

(*4) At power-off state after installation

Vibration displacement should be less than 2.5 mm.

(*5) Input voltages are specified at the drive connector side, during drive ready state.

(*6) High frequency noise (over 20MHz) is less than 100 mVp-p.

2.1.4Error rate

Errors detected during initialization and replaced by alternate block assignments are not included in the error rate. Data blocks to be accessed should be distributed over the disk medium equally.

(1)Unrecoverable error rate

Errors which cannot be recovered within 63 retries and ECC correction should not exceed 1 per 1015 bits.

Data loss

For MAP series, Reed Solomon codes are applied for their ECC. The sector-data is divided into 6 interleaving sectors, and ECC is performed in each sector where the maximum number of errors (up to 5 byte) can be corrected. [Total maximum byte: 5 byte ⋅ 6 ( interleave) = 30 byte]

If the error of read sector keeps allowable error byte number, correction is performed. However, if error byte exceeds its allowable number, correction may not be performed properly.

(2)Positioning error rate

Positioning errors which can be recovered by one retry should be 10 or less per 108 seeks.

2.1.5Reliability

(1)Mean Time Between Failures (MTBF)

MTBF of the IDD during its life time is 1,2000,000 hours (operating: 24 hours/day, 7 days/week

average DE surface temperature: 50°C or less).

C141-E163 2-5