Data storage device computing notch filters for multiple temperatures
A data storage device is disclosed comprising a head actuated over the disk. A first notch filter is calibrated at a first temperature, and a second notch filter is computed for a second temperature based on the first notch filter and a first delta temperature between the first temperature and the second temperature. The second notch filter is computed by transforming a continuous-time transfer function of the first notch filter adjusted by the first delta temperature into a discrete-time transfer function of the second notch filter.
1. A data storage device comprising:
a disk;
a head actuated over the disk; and
control circuitry configured to:
calibrate a first notch filter at a first temperature; and
compute a second notch filter for a second temperature based on the first notch filter and a first delta temperature between the first temperature and the second temperature,
wherein the second notch filter is computed by transforming a continuous-time transfer function of the first notch filter adjusted by the first delta temperature into a discrete-time transfer function of the second notch filter.
2. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to:
measure a temperature of the data storage device;
select between the first notch filter and the second notch filter based on the measured temperature; and
actuate the head over the disk using the selected notch filter.
3. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to:
measure a temperature of the data storage device;
compute a third notch filter by interpolating at least one coefficient of the first notch filter and the second notch filter based on the measured temperature; and
actuate the head over the disk using the third notch filter.
4. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to:
compute a shift of a center frequency of the first notch filter due to the delta temperature; and
compute the second notch filter based on the shift of the center frequency.
5. The data storage device as recited in claim 1 , wherein the control circuitry is further configured to:
calibrate the first notch filter during a manufacturing procedure; and
compute the second notch filter during a power-on procedure.
6. The data storage device as recited in claim 1 , wherein:
the control circuitry is further configured to compute a third notch filter for a third temperature based on the first notch filter and a second delta temperature between the first temperature and the third temperature; and
the third notch filter is computed by transforming a continuous-time representation of the first notch filter adjusted by the second delta temperature into a discrete-time representation of the third notch filter.
7. A data storage device comprising:
a disk;
a head actuated over the disk; and
control circuitry configured to:
calibrate a first notch filter at a first temperature;
compute a second notch filter based on a center frequency shift of the first notch filter due to a first temperature delta between the first temperature and a second temperature,
wherein the second notch filter is computed by transforming a continuous-time transfer function of the first notch filter adjusted by the first delta temperature into a discrete-time transfer function of the second notch filter.
8. The data storage device as recited in claim 7 , wherein the control circuitry is further configured to:
measure a temperature of the disk drive;
select between the first notch filter and the second notch filter based on the measured temperature; and
actuate the head over the disk using the selected notch filter.
9. The data storage device as recited in claim 7 , wherein the control circuitry is further configured to:
measure a temperature of the disk drive;
compute a third notch filter by interpolating at least one coefficient of the first notch filter and the second notch filter based on the measured temperature; and
actuate the head over the disk using the third notch filter.
10. The data storage device as recited in claim 7 , wherein the control circuitry is further configured to:
calibrate the first notch filter during a manufacturing procedure; and
compute the second notch filter during a power-on procedure.
11. The data storage device as recited in claim 7 , wherein:
the control circuitry is further configured to compute a third notch filter based on a center frequency shift of the first notch filter due to a second temperature delta between the first temperature and a third temperature; and
the third notch filter is computed by transforming a continuous-time representation of the first notch filter adjusted by the second delta temperature into a discrete-time representation of the third notch filter.
12. A data storage device comprising:
a disk;
a head actuated over the disk; and
a means for calibrating a first notch filter at a first temperature; and
a means for computing a second notch filter for a second temperature based on the first notch filter and a delta temperature between the first temperature and the second temperature.
13. The data storage device as recited in claim 12 , further comprising:
a means for measuring a temperature of the data storage device;
a means for selecting between the first notch filter and the second notch filter based on the measured temperature; and
a means for actuating the head over the disk using the selected notch filter.
14. The data storage device as recited in claim 12 , further comprising:
a means for measuring a temperature of the data storage device;
a means for computing a third notch filter by interpolating at least one coefficient of the first notch filter and the second notch filter based on the measured temperature; and
a means for actuating the head over the disk using the third notch filter.
15. The data storage device as recited in claim 12 , further comprising:
a means for computing a shift of a center frequency of the first notch filter due to the delta temperature; and
a means for computing the second notch filter based on the shift of the center frequency.
16. The data storage device as recited in claim 12 , further comprising:
a means for calibrating the first notch filter during a manufacturing procedure; and
a means for computing the second notch filter during a power-on procedure.
17. The data storage device as recited in claim 12 , further comprising a means for computing a third notch filter for a third temperature based on the first notch filter and a delta temperature between the first temperature and the third temperature.