| 摘要 |
The invention relates to an emergency power off (EPO) power island for saving critical data to nonÂ-volatile memory in the event of an EPO condition, for use in a hard-disk drive (HDD) storage device. A hard-disk drive controller (HDC) features an EPO power island. The EPO power island includes a controller for detecting an EPO condition and internal memory. A voltage regulator supplies power from hard-disk spindle motor back EMF only to the EPO power island and the non-volatile memory. Thus, the remainder of the HDC is isolated from the EPO power island so that it will not corrupt the data as the HDC's power supply is decaying. Using the power provided by the voltage regulator, the EPO power island transfers critical data from the internal memory of the power island to a non-volatile memory external to the island, such as to a flash memory chip. The power island controller can suspend signal transmissions which would change the data internal to the power island. The power island can have an oscillator which generates a reference clock signal for the EPO power island, the frequency of the clock signal being lower than that of the system clock of the hard-disk controller. |
