Temperature dependent disc drive parametric configuration

• US 6,078,455 A
• Filed: 07/09/1999
• Issued: 06/20/2000
• Est. Priority Date: 06/13/1997
• Status: Expired due to Fees

• Current Assignee: Seagate Technology LLC (Seagate Technology Holdings Plc)
• Original Assignee: Seagate Technology plc (Seagate Technology Holdings Plc)
• Inventors: Metzner, Ronald D., Enarson, Karl L., Walker, Timothy T., Ukani, Anish A.
• Primary Examiner(s): Burgess, Glenton B.
• Assistant Examiner(s): WONG, KIN C
• Application Number:
  US09/350,832
• Time in Patent Office: 347 Days
• Field of Search: 360/78.06, 360/77.04, 360/66-68, 360/78.04, 360/78.05, 360/97.02, 360/69, 369/116
• US Class Current: 360/68
• CPC Class Codes: G11B 2005/001 Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure
• CPC Class Codes: G11B 2220/20 Disc-shaped record carriers
• CPC Class Codes: G11B 25/043 using rotating discs
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06
• CPC Class Codes: G11B 33/144 by detection, control, regulation of the temperature
• CPC Class Codes: G11B 5/012 Recording on, or reproducing or erasing from, magnetic disks G11B17/00, G11B19/00 take precedence
• CPC Class Codes: G11B 5/5565 system adaptation for compensation of variations of physical parameters, e.g. temperature

Abstract

A method and apparatus are disclosed for optimizing operational performance of a disc drive through temperature dependent parametric configuration. A plurality of parameter sets corresponding to a plurality of predefined contiguous operational temperature ranges of the disc drive are initially established. During operation of the disc drive, a temperature sensor is used to periodically measure the temperature of the drive. The operational temperature range in which the measured temperature falls is identified, and the disc drive utilizes the parameter set corresponding to the identified operational temperature range.

Claims

1. A method for optimizing operational performance of a disc drive, comprising steps of:

(a) identifying a boundary temperature to establish a first temperature zone comprising a plurality of temperatures which sequentially extend below the boundary temperature and a second temperature zone comprising a plurality of temperatures which sequentially extend above the boundary temperature;

(b) operating the disc drive while having an operational temperature which falls within the first temperature zone and selectively varying parameter values utilized by selected electronic circuitry of the disc drive;

(c) selecting a first set of the parameter values selectively varied during step (b) which achieves a desired level of operational performance by the disc drive, the first set of the parameter values stored for subsequent use by the selected electronic circuitry of the disc drive when the disc drive is operated while having an operational temperature equal to any selected temperature from the first temperature zone,

(d) selecting a second set of the parameter values which achieve a desired level of operational performance by the drive, the second set of the parameter values stored for subsequent use by the selected electronic circuitry of the disc drive when the disc drive is operated while having an operational temperature equal to any selected temperature from the second temperature zone;

(e) measuring a first operational temperature of the disc drive and loading a selected one of the first or second sets of the parameter values in relation to the temperature zone in which the first operational temperature falls;

(f) selecting a time interval comprising an increment of elapsed time;

(g) initiating a timer which provides an indication of the passage of each successive time interval; and

(h) at the conclusion of each successive time interval, loading the appropriate set of the parameter values from the first and second set of the parameter values corresponding to the temperature zone in which an existing operational temperature of the disc drive falls, independently of operations concurrently performed by the disc drive.

2. The method of claim 1, further comprising a step of:

(i) prior to step (d), operating the disc drive while having an operational temperature which falls within the second temperature zone and selectively varying the parameter values utilized by the selected electronic circuitry of the disc drive.

3. The method of claim 1, wherein step (h) further comprises steps of:

(h1) identifying a temperature boundary increment;

(h2) combining the temperature boundary increment with the boundary temperature to obtain an increased boundary temperature greater than the boundary temperature, so that the disc drive switches from the first to the second set of the parameter values only after the existing operational temperature equals or exceeds the increased boundary temperature; and

(h3) combining the temperature boundary increment with the boundary temperature to obtain a decreased boundary temperature less than the boundary temperature, so that the disc drive switches from the second to the first set of the parameter values only after the existing operational temperature is equal to or less than the decreased boundary temperature.

4. The method of claim 1, wherein the boundary temperature of step (a) is characterized as a first boundary temperature, and wherein the method further comprises steps of:

(i) identifying a second boundary temperature greater than the first boundary temperature to establish a third temperature zone comprising a plurality of temperatures which sequentially extend above the second boundary temperature, wherein the second temperature zone is bounded by the first and second boundary temperatures;

(j) selecting a third set of the parameter values which achieves a desired level of operational performance by the disc drive, the third set of the parameter values stored for subsequent use by the selected electronic circuitry of the disc drive when the disc drive is operated while having an operational temperature equal to any selected temperature from the third temperature zone; and

wherein step (h) further loads the appropriate set of parameters from the first, second and third sets of the parameter values.

5. The method of claim 1, wherein the first boundary temperature is a value less than 20 degrees Celsius and the second boundary temperature is a value greater than 20 degrees Celsius.

6. A disc drive, comprising:

a head controllably positionable adjacent a rotatable disc;

a read/write channel which controls transfer of data between the disc and a host computer in which the disc drive is mountable;

a servo circuit which controls position of the head;

a temperature sensor which provides an indication of operational temperature of the disc drive; and

a control processor, responsive to the temperature sensor, the read/write channel and the servo circuit, which provides top level control of the disc drive, the control processor having associated programming to;

(a) identify a boundary temperature to establish a first temperature zone comprising a plurality of temperatures which sequentially extend below the boundary temperature and a second temperature zone comprising a plurality of temperatures which sequentially extend above the boundary temperature;

(b) perform data transfer operations while the temperature sensor indicates an operational temperature which falls within the first temperature zone and selectively vary parameter values utilized by the read/write channel and the servo circuit;

(c) select a first set of the parameter values selectively varied during step (b) which achieves a desired level of operational performance by the read/write channel and the servo circuit, the first set of the parameter values stored for subsequent use when the disc drive is operated while having an operational temperature equal to any selected temperature from the first temperature zone;

(d) select a second set of the parameter values selectively which achieve a desired level of operational performance by the read/write channel and the servo circuit, the second set of the parameter values stored for subsequent use when the disc drive is operated while having an operational temperature equal to any selected temperature from the second temperature zone;

(e) measure a first operational temperature of the disc drive and load a selected one of the first or second sets of the parameter values in relation to the temperature zone in which the first operational temperature falls;

(f) select a time interval comprising an increment of elapsed time;

(g) initiate a timer which provides an indication of the passage of each successive time interval; and

(h) at the conclusion of each successive time interval, load the appropriate set of the parameter values from the first and second set of the parameter values corresponding to the temperature zone in which an existing operational temperature of the disc drive falls independently of operations concurrently performed by the disc drive.

7. The disc drive of claim 6, wherein the control processor has further programming to:

(h1) identify a temperature boundary increment;

(h2) combine the temperature boundary increment with the boundary temperature to obtain an increased boundary temperature greater than the boundary temperature, so that the disc drive switches from the first to the second set of the parameter values only after the existing operational temperature equals or exceeds the increased boundary temperature; and

(h3) combine the temperature boundary increment with the boundary temperature to obtain a decreased boundary temperature less than the boundary temperature, so that the disc drive switches from the second to the first set of the parameter values only after the existing operational temperature is equal to or less than the decreased boundary temperature.

8. The disc drive of claim 6, wherein the boundary temperature of programming step (a) is characterized as a first boundary temperature, and wherein the control processor has further programming to:

(i) identify a second boundary temperature greater than the first boundary temperature to establish a third temperature zone comprising a plurality of temperatures which sequentially extend above the second boundary temperature, wherein the second temperature zone is bounded by the first and second boundary temperatures;

(j) select a third set of the parameter values which achieves a desired level of operational performance by the disc drive, the third set of the parameter values stored for subsequent use by the selected electronic circuitry of the disc drive when the disc drive is operated while having an operational temperature equal to any selected temperature from the third temperature zone; and

wherein the programming step (h) further loads the appropriate set of parameters from the first, second and third sets of parameters.

9. The disc drive of claim 8, wherein the first boundary temperature is a value less than 20 degrees celsius and the second boundary temperature is a value greater than 20 degrees celsius.