Data storage device employing cascaded voltage regulators during power failure
View Patent ↗A data storage device is disclosed comprising a non-volatile memory and control circuitry comprising an interface operable to receive a supply voltage, and a capacitor. An operating voltage regulator converts the supply voltage into an operating voltage used to operate the non-volatile memory. The supply voltage is used to charge the capacitor to a capacitor voltage higher than the supply voltage, and during a power failure, a backup voltage regulator converts the capacitor voltage into a backup voltage substantially equal to the supply voltage. The operating voltage regulator converts the backup voltage into the operating voltage used to operate the non-volatile memory.
1. A data storage device comprising:
a non-volatile memory; and
control circuitry comprising an interface operable to receive a supply voltage, and
a capacitor, wherein the control circuitry is operable to:
use an operating voltage regulator to convert the supply voltage into an operating voltage used to operate the non-volatile memory;
use the supply voltage to charge the capacitor to a capacitor voltage higher than the supply voltage; and
during a power failure:
use a backup voltage regulator to convert the capacitor voltage into a backup voltage substantially equal to the supply voltage; and
use the operating voltage regulator to convert the backup voltage into the operating voltage used to operate the non-volatile memory.
2. The data storage device as recited in claim 1 , wherein the control circuitry is operable to:
boost the supply voltage to a boosted voltage higher than the supply voltage; and
charge the capacitor with the boosted voltage.
3. The data storage device as recited in claim 2 , further comprising a microactuator operable to actuate a head radially over a disk, wherein the control circuitry is operable to control the microactuator using the boosted voltage.
4. The data storage device as recited in claim 1 , further comprising a microactuator wherein during the power failure the control circuitry is operable to:
boost the backup voltage to a boosted voltage higher than the backup voltage; and
control the microactuator using the boosted voltage.
5. The data storage device as recited in claim 1 , wherein the operating voltage is lower than the backup voltage.
6. The data storage device as recited in claim 1 , wherein the operating voltage is higher than the backup voltage.
7. The data storage device as recited in claim 6 , further comprising a voice coil motor (VCM) operable to actuate a head radially over a disk, wherein the control circuitry is operable to control the VCM using the operating voltage.
8. The data storage device as recited in claim 1 , wherein the interface receives the supply voltage from a host.
9. The data storage device as recited in claim 1 , wherein the non-volatile memory comprises a disk.
10. The data storage device as recited in claim 1 , wherein the non-volatile memory comprises a semiconductor memory.
11. A method of operating a data storage device comprising a non-volatile memory, an interface operable to receive a supply voltage, and a capacitor, the method comprising:
using an operating voltage regulator to convert the supply voltage into an operating voltage used to operate the non-volatile memory;
using the supply voltage to charge the capacitor to a capacitor voltage higher than the supply voltage; and
during a power failure:
using a backup voltage regulator to convert the capacitor voltage into a backup voltage substantially equal to the supply voltage; and
using the operating voltage regulator to convert the backup voltage into the operating voltage used to operate the non-volatile memory.
12. The method as recited in claim 11 , further comprising:
boosting the supply voltage to a boosted voltage higher than the supply voltage; and
charging the capacitor with the boosted voltage.
13. The method as recited in claim 12 , wherein the data storage device further comprises a microactuator operable to actuate a head radially over a disk, the method further comprising controlling the microactuator using the boosted voltage.
14. The method as recited in claim 11 , wherein the data storage device further comprises a microactuator and during the power failure the method further comprising:
boosting the backup voltage to a boosted voltage higher than the backup voltage; and
controlling the microactuator using the boosted voltage.
15. The method as recited in claim 11 , wherein the operating voltage is lower than the backup voltage.
16. The method as recited in claim 11 , wherein the operating voltage is higher than the backup voltage.
17. The method as recited in claim 16 , wherein the data storage device further comprises a voice coil motor (VCM) operable to actuate a head radially over a disk, the method further comprising controlling the VCM using the operating voltage.
18. The method as recited in claim 11 , wherein the interface receives the supply voltage from a host.
19. The method as recited in claim 11 , wherein the non-volatile memory comprises a disk.
20. The method as recited in claim 11 , wherein the non-volatile memory comprises a semiconductor memory.