Memory Systems and Methods

Abstract

The memory system includes a temperature sensor, a capacitor, a power supply circuit, a volatile first memory, a non-volatile second memory, and a controller. The power supply circuit generates electricity using the electrical energy stored in the capacitor when power is off. The controller performs a capacitance test at least once at different times. During the capacitance test, the controller acquires the capacitance value and the temperature value of the capacitor. When the temperature value is the first value, the controller sets the second value as the capacitance threshold; when the temperature value is the third value, which is lower than the first value, the controller sets the fourth value, which is smaller than the second value, as the capacitance threshold. The controller switches from the first operating mode to the second operating mode in response to the capacitance value becoming smaller than the capacitance threshold.

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