Method of tagging calibration results with temperature, time and/or voltage
View Patent ↗The results of a calibration can be stored in a hard disk drive along with a hard disk condition indication. After the hard disk is re-started, it can be checked to see whether the stored hard disk condition indication is sufficiently close to a current hard disk condition indication. If the condition indication is sufficiently close, the stored calibration results can be used.
1. A method of operating a hard disk drive comprising:
calibrating all or a portion of the hard disk drive;
storing the calibration results along with a hard disk condition indication in a non-volatile memory of the hard disk drive; and
after a later power-up, using the stored hard disk condition indication to determine whether to recalibrate all or a part of the hard disk drive.
2. The method of claim 1 , wherein, after the later power-up, a later hard disk condition indication is compared to the hard disk condition indication.
3. The method of claim 2 , wherein based on the comparison it is determined determine whether to recalibrate all or a part of the hard drive.
4. The method of claim 1 , wherein if the later hard disk conditions are close to the stored hard disk conditions a recalibration is not done.
5. The method of claim 1 , wherein the stored calibration results are used if a recalibration is not done.
6. The method of claim 1 , wherein the stored hard disk condition indication indicates temperature.
7. The method of claim 6 , wherein if, after a later power-up, the temperature is within a preset range from the temperature indicated by the stored hard disk condition indication, recalibration is not done and the stored calibration results are used.
8. The method of claim 6 , wherein the hard disk drive includes a temperature sensor.
9. The method of claim 1 , wherein the stored hard disk condition indication indicates a time measurement.
10. The method of claim 9 , wherein the time measurement is a measurement of hard disk time-on.
11. The method of claim 10 , wherein the time measurement is a measurement of time that a bias current is applied to read sensor.
12. The method of claim 9 , wherein if, after a later power-up, the time measurement is within a preset range of the time measurement indicated by the stored hard disk condition indication, recalibration is not done and the stored calibration results are used.
13. The method of claim 1 , wherein the hard disk condition indication is a battery indication.
14. The method of claim 13 , wherein the battery indication is a battery voltage indication.
15. The method of claim 1 , wherein the hard disk condition indication is a function of temperature, time, and/or battery voltage.
16. The method of claim 1 , wherein the calibration results relate to bias.
17. The method of claim 1 , wherein the calibration results relate to KT/J.
18. The method of claim 1 , wherein the calibration results relate to the runout harmonics.
19. The method of claim 1 , wherein the calibration results relate to the write current.
20. The method of claim 1 , wherein the calibration results relate to the PES calibration.
21. The method of claim 1 , wherein the non-volatile memory is a disk of the hard disk drive.
22. The method of claim 1 , wherein the non-volatile memory is a flash memory.
23. The method of claim 1 , wherein the non-volatile memory is NVRAM.