Predictive failure analysis of thermal flying height control system and method
View Patent ↗A method for predicting the failure of a data storage device having a slider heater is disclosed. For slider heaters exhibiting a decreasing resistance aging characteristic, a failure warning is produced when heater resistance suddenly increases 2 to 5%, or dR/dt changes sign from negative to positive. For slider heaters exhibiting an increasing resistance aging characteristic, a failure warning is produced when the heater resistance suddenly drops 2 to 5%, or dR/dt changes sign from positive to negative. Additionally, random changes in heater resistance exceeding nominal measurement error may also be utilized to produce a failure warning. This method provides advance warning of potential data read/write errors well before the open circuit failure of the slider heater occurs.
1. A method for predicting the failure of a data storage device having a slider heater, comprising:
measuring a first slider heater resistance value;
measuring a second slider heater resistance value subsequent to measuring said first slider heater resistance value, said second slider heater value being less than said first slider resistance value;
measuring a third slider heater resistance value subsequent to measuring said second slider heater resistance value; and,
providing a failure warning when said third slider resistance value is greater than said second slider resistance value.
2. The method as recited in claim 1 , wherein a first time interval between measuring said first slider heater resistance value and said second slider heater resistance value is greater than a second time interval between measuring said second slider heater resistance value and said third slider heater resistance value.
3. The method as recited in claim 2 , wherein said first time interval is between 0.1 and 10 minutes.
4. The method as recited in claim 2 , wherein said second time interval is between 0.1 and 10 seconds.
5. The method as recited in claim 1 , wherein the difference between said third slider heater resistance value and said second slider heater resistance value is between 2% and 5% of said second slider heater resistance value.
6. The method as recited in claim 1 , wherein said slider heater is burned in prior to measuring said first slider heater resistance value.
7. A method for predicting the failure of a data storage device having a slider heater, comprising:
measuring a first slider heater resistance value;
measuring a second slider heater resistance value subsequent to measuring said first slider heater resistance value, said second slider heater value being greater than said first slider resistance value;
measuring a third slider heater resistance value subsequent to measuring said second slider heater resistance value; and,
providing a failure warning when said third slider heater resistance value is less than said second slider heater resistance value.
8. The method as recited in claim 7 , wherein a first time interval between measuring said first slider heater resistance value and said second slider heater resistance value is greater than a second time interval between measuring said slider heater resistance value and said third slider heater resistance value.
9. The method as recited in claim 7 , wherein said first time interval is between 0.1 and 10 minutes.
10. The method as recited in claim 7 , wherein said second time interval is between 0.1 and 10 seconds.
11. The method as recited in claim 7 , wherein the difference between said second slider heater resistance value and said third slider heater resistance value is between 2% and 5% of said second slider heater resistance value.
12. The method as recited in claim 7 , wherein said slider heater is burned in prior to measuring said first slider heater resistance value.