Patent ID: 8242633

Claim:
A method for protecting a non-volatile semiconductor storage device during a power failure of a power supply, said method comprising: during normal operation of the device, dynamically detecting a status of an energy storage unit and controlling an external power input to charge an energy storage unit according to the status to ensure sufficient backup electrical energy for the energy storage unit; upon detecting an abnormality of the power supply, discharging the energy storage unit for providing power to the semiconductor storage device; and adjusting a charge/discharge rate of the energy storage unit so as to ensure that the energy storage unit charges at a rate that is no less than the rate of discharge; and wherein adjusting a charge rate of the energy storage unit includes intermittently storing energy in an inductor and discharging said energy to the energy storage unit; and adjusting a discharge rate of the energy storage unit includes intermittently storing energy in an inductor and discharging said energy to the storage device.