Browse Prior Art Database

HDD reliability enhancement at low temperature

IP.com Disclosure Number: IPCOM000013598D
Original Publication Date: 1999-Dec-01
Included in the Prior Art Database: 2003-Jun-18
Document File: 1 page(s) / 26K

Publishing Venue

IBM

Related People

Masaomi Ikeda: AUTHOR [+5]

Abstract

A program is disclosed that HDD reliability enhancement at low temperature. HDD's spec. guarantee an operation between 5degC to 55degC today.

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HDD reliability enhancement at low temperature

    A program is disclosed that HDD reliability enhancement at low temperature.
HDD's spec. guarantee an operation between 5degC to 55degC today.

    But there are many requests to use HDD at lower temperature. In such cases, to
start up HDD is the first concern. This is called as POR ( Power On Reset).

    Following two conditions are required to guarantee POR. 1) It's possible to
spin up spindle motor as usual. 2) It's possible to read/write as usual.

This program is disclosed an improvement of the case 2).

    Many cases of problems about POR are caused by "chilled IC chip" such as
channel and arm electronics (AE) at low temperature.

    During read/write operation, signals on the disk are picked up by head and got
into channel through AE.

    So the first condition which required to avoid such a problem is that AE works
correctly right after power on.

    But there are some cases that it takes much time to complete POR at low temp
than usual because of chilled AE.

    This is the one of the reason why HDD cannot be guaranteed operation at low
temp such as -5deg or so.

    To improve the reliability of AE at low temperature, It is effective to pour
much electric current into the chip to heat it up.

    And it's possible to do that by write operation. Our recommendation is as
follows.

1) Do Dummy write on the ramp before loading on the disk.
2) At that time, select Gang Write Mode of AE to write by 2 heads at the
same time.

           ( Gang Write Mode is usually used for writ...