Memory storage apparatus include a non-volatile memory for storing data and a power management unit configured to sense a level of an external power supply and to predict a loss of the external power supply. A power-polling time control circuit is configured to control a time when a voltage level sourced from the external power supply is reduced below a predetermined level after loss of the external power supply. A control logic controls read and/or write operations of the non-volatile memory responsive to a prediction of loss of the external power supply from the power management unit.