Magnetic-recording head with first thermal fly-height control element and embedded contact sensor element configurable as second thermal fly-height control element
A magnetic-recording head with a first thermal fly-height control (TFC) element and an embedded contact sensor element (ECSE) configurable as a second TFC element. The magnetic-recording head includes a write element, a read element, a first heater element, and an ECSE. The write element is configured for writing data to a magnetic-recording disk. The read element is configured for reading data from the magnetic-recording disk. The first heater element is configured as a first TFC element to coarsely adjust a fly-height of the magnetic-recording head with respect to the magnetic recording disk. The ECSE is configured to detect a contact with the magnetic-recording disk, and to function as a second heater element that is configured as a second TFC element to finely adjust the fly-height. The first heater element is configured with a first stroke-length larger than a second stroke-length of the second heater element for adjusting the fly-height.
1. A magnetic-recording head with a first thermal fly-height control element and an embedded contact sensor element configurable as a second thermal fly-height control element, said magnetic-recording head comprising:
a write element configured for writing data to a magnetic-recording disk;
a read element configured for reading back data from said magnetic-recording disk written by said write element;
a first heater element configured as said first thermal fly-height control element to coarsely adjust a fly-height of said magnetic-recording head with respect to said magnetic recording disk; and
said embedded contact sensor element configured to detect a contact with said magnetic-recording disk, and configured to function as said second heater element, said second heater element configured as said second thermal fly-height control element to finely adjust said fly-height;
wherein said first heater element is configured to produce a first stroke-length larger than a second stroke-length of said second heater element for adjusting said fly-height.
2. The magnetic-recording head of claim 1 , wherein said embedded contact sensor element is disposed in close proximity to an air-bearing surface of said magnetic-recording head.
3. The magnetic-recording head of claim 1 , wherein said embedded contact sensor element is disposed in closer proximity to said write element than said read element.
4. The magnetic-recording head of claim 1 , wherein said first stroke-length of said first heater element is about 10 nm.
5. The magnetic-recording head of claim 1 , wherein said wherein said second stroke-length of said second heater element is about 0.5 nm.
6. The magnetic-recording head of claim 1 , wherein said embedded contact sensor element is configured to provide sensitivity for detection of a head-disk-interference event that causes an increase of temperature of said embedded contact sensor element on an order of at least about 1%.
7. An arm-electronics module for a magnetic-recording head with a first thermal fly-height control element and an embedded contact sensor element configurable as a second thermal fly-height control element, said arm-electronics module comprising:
a substrate;
a write-signal amplifier configured to amplify a write signal sent to a write element of said magnetic-recording head;
a read-signal amplifier configured to amplify a read-back signal sent from a read element of said magnetic-recording head;
a first heater-element power supply configured to provide power in at least one first heater-element power increment to said first heater element of said magnetic-recording head;
a second heater-element power supply configured to provide power to said embedded contact sensor element of said magnetic-recording head; and
wherein said write-signal amplifier, said read-signal amplifier, said first heater-element power supply and said second heater-element power supply are fabricated on said substrate.
8. The arm-electronics module of claim 7 , further comprising:
a control unit configured to supply control signals to said write-signal amplifier, said read-signal amplifier, said first heater-element power supply and said second heater-element power supply.
9. The arm-electronics module of claim 7 , further comprising:
a first-heater element electrical-resistance measurement circuit for said first heater element, said first-heater element electrical-resistance measurement circuit fabricated on said substrate.
10. The arm-electronics module of claim 9 , further comprising:
a control unit configured to supply control signals to first-heater element electrical-resistance measurement circuit.
11. The arm-electronics module of claim 7 , further comprising:
a second-heater element electrical-resistance measurement circuit for said embedded contact sensor element, said second-heater element electrical-resistance measurement circuit fabricated on said substrate.
12. The arm-electronics module of claim 11 , wherein said second-heater element electrical-resistance measurement circuit for said embedded contact sensor element is configured to measure electrical-resistance changes of said embedded contact sensor element on an order of about 0.1%.
13. The arm-electronics module of claim 11 , further comprising:
a control unit configured to supply control signals to second-heater element electrical-resistance measurement circuit.
14. The arm-electronics module of claim 7 , wherein said second heater-element power supply is configured to supply a second maximum power to said embedded contact sensor element that is less than a first maximum power supplied to said first heater element by said first heater-element power supply, but greater than said first heater-element power increment supplied to said first heater element by said first heater-element power supply.
15. The arm-electronics module of claim 7 , further comprising:
a monolithic integrated circuit.
16. A hard-disk drive, comprising:
at least one magnetic-recording disk;
at least one magnetic-recording head comprising:
a write element configured for writing data to a magnetic-recording disk;
a read element configured for reading back data from said magnetic-recording disk written by said write element;
a first heater element configured as a first thermal fly-height control element to coarsely adjust a fly-height of said magnetic-recording head with respect to said magnetic recording disk; and
an embedded contact sensor element configured to detect contact with said magnetic-recording disk, and configured to function as a second heater element, said second heater element configured as a second thermal fly-height control element to finely adjust said fly-height;
wherein said first heater element is configured to produce a first stroke-length larger than a second stroke-length of said second heater element for adjusting said fly-height;
wherein said magnetic-recording head is configured to read data from, and to write data to, said magnetic-recording disk; and
an arm-electronics module comprising:
a substrate;
a write-signal amplifier configured to amplify a write signal sent to a write element of said magnetic-recording head;
a read-signal amplifier configured to amplify a read-back signal sent from a read element of said magnetic-recording head;
a first heater-element power supply configured to provide power in at least one first heater-element power increment to said first heater element of said magnetic-recording head;
a second heater-element power supply configured to provide power to said embedded contact sensor element of said magnetic-recording head; and
wherein said write-signal amplifier, said read-signal amplifier, said first heater-element power supply and said second heater-element power supply are fabricated on said substrate.
17. The hard-disk drive of claim 16 , wherein said first stroke-length of said first heater element is about 10 nm.
18. The hard-disk drive of claim 16 , wherein said wherein said second stroke-length of said second heater element is about 0.5 nm.
19. The hard-disk drive of claim 16 , wherein said embedded contact sensor element is configured to provide sensitivity for detection of a head-disk-interference event that causes an increase of temperature of said embedded contact sensor element on an order of at least about 1%.
20. The hard-disk drive of claim 16 , wherein said second-heater element electrical-resistance measurement circuit for said embedded contact sensor element is configured to measure electrical-resistance changes of said embedded contact sensor element on an order of about 0.1%.
21. The hard-disk drive of claim 16 , wherein said second heater-element power supply is configured to supply a second maximum power to said embedded contact sensor element that is less than a first maximum power supplied to said first heater element by said first heater-element power supply, but greater than said first heater-element power increment supplied to said first heater element by said first heater-element power supply.