Granted Patent B1

US 8,792,200 · App. 14/034,514 · Granted Jul 29, 2014

Abstract

Claims (37)

1. A disk drive comprising:

a disk;

a head actuated over the disk, the head comprising a read element radially offset from a write element; and

control circuitry configured to:

measure a temperature;

generate an operating write offset based on the measured temperature;

write data to a target radial location on the disk by radially offsetting the write element based on the operating write offset;

generate an operating read offset based on the target radial location on the disk; and

read the data from the disk by radially offsetting the read element based on the operating read offset.

2. The disk drive as recited in claim 1 , wherein the control circuitry is further configured to generate the operating write offset as a function of the temperature.

3. The disk drive as recited in claim 2 , wherein the control circuitry is further configured to:

measure a first temperature write offset at a first temperature;

measure a second temperature write offset at a second temperature; and

generate the function based on the first temperature write offset and second temperature write offset.

4. The disk drive as recited in claim 3 , wherein the control circuitry is further configured to generate a write jog table using the function.

5. The disk drive as recited in claim 1 , wherein the control circuitry is further configured to generate the operating write offset based on the target radial location.

6. The disk drive as recited in claim 1 , wherein when reading data from the disk using the operating read offset fails, the control circuitry is further configured to retry the read after adjusting the operating read offset by a delta.

7. The disk drive as recited in claim 1 , wherein the operating write offset compensates for a thermal deformation of a component of the disk drive.

8. The disk drive as recited in claim 7 , wherein the component comprises the disk.

9. The disk drive as recited in claim 7 , wherein the component comprises a head stack assembly.

10. A method of operating a disk drive comprising:

measuring a temperature;

generating an operating write offset based on the measured temperature;

writing data to a target radial location on a disk by radially offsetting a write element based on the operating write offset;

generating an operating read offset based on the target radial location on the disk; and

reading the data from the disk by radially offsetting the read element based on the operating read offset.

11. The method as recited in claim 10 , further comprising generating the operating write offset as a function of the temperature.

12. The method as recited in claim 11 , further comprising:

measuring a first temperature write offset at a first temperature;

measuring a second temperature write offset at a second temperature; and

generating the function based on the first temperature write offset and second temperature write offset.

13. The method as recited in claim 12 , further comprising generating a write jog table using the function.

14. The method as recited in claim 10 , further comprising generating the operating write offset based on the target radial location.

15. The method as recited in claim 10 , wherein when reading data from the disk using the operating read offset fails, the method further comprises retrying the read after adjusting the operating read offset by a delta.

16. The method as recited in claim 10 , wherein the operating write offset compensates for a thermal deformation of a component of the disk drive.

17. The method as recited in claim 16 , wherein the component comprises the disk.

18. The method as recited in claim 16 , wherein the component comprises a head stack assembly.

Assignments (8)