Auxiliary power supply, operating method of the auxiliary power supply and storage device including the auxiliary power supply

1. An auxiliary power supply, comprising:

an auxiliary power storage configured to store power that is input to the auxiliary power supply; and

a control circuit configured to:

determine a peak current level of the auxiliary power storage as a main level;

charge, for a reference time amount after the power is input to the auxiliary power supply, the auxiliary power storage by a first current source having the main level;

determine, after the reference time amount, that the auxiliary power supply is in a slow charging state when a voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount is lower than a reference voltage level;

change, in response to determining that the auxiliary power supply is in the slow charging state, the peak current level from the main level to a backup level that is greater than the main level; and

charge the auxiliary power storage by a second current source having the backup level.

2. The auxiliary power supply of claim 1 , wherein the control circuit changes, in response to determining that the auxiliary power supply is in the slow charging state, the peak current level from the main level to the backup level when a charge limit time amount elapses after the power is input to the auxiliary power supply.

3. The auxiliary power supply of claim 1 , wherein the auxiliary power storage includes a polymer capacitor.

4. The auxiliary power supply of claim 1 , wherein the control circuit is further configured to change, when the voltage level that is charged to the auxiliary power storage by the second current source reaches a target voltage level, the peak current level from the backup level to the main level.

5. The auxiliary power supply of claim 1 , wherein the control circuit is further configured to:

periodically generate a switching signal that operates a switching element, and

reduce, in response to determining that the auxiliary power supply is in the slow charging state, a period of the generating of the switching signal.

6. The auxiliary power supply of claim 1 , wherein the control circuit includes a voltage monitoring component configured to:

monitor the voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount, and

compare the voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount with the reference voltage level.

7. The auxiliary power supply of claim 1 , wherein the control circuit includes a counter that calculates the reference time amount.

8. A method of operating an auxiliary power supply, the method comprising:

inputting power to the auxiliary power supply;

determine a peak current level of the auxiliary power storage included the auxiliary power supply in as a main level;

charging, for a reference time amount after the power is input to the auxiliary power supply, the auxiliary power supply by a first current source having the main level;

determining, after the reference time amount, that the auxiliary power supply is in a slow charging state when a voltage level that is charged to the auxiliary power supply by the first current source for the reference time amount is lower than a reference voltage level;

changing, in response to determining that the auxiliary power supply is in the slow charging state, the peak current level from the main level to a backup level that is greater than the main level; and

charging the auxiliary power supply by a second current source having the backup level.

9. The method of claim 8 , wherein the auxiliary power storage includes a polymer capacitor.

10. The method of claim 8 , further comprising changing, when the voltage level that is charged to the auxiliary power supply by the second current source reaches the target voltage level, the peak current level from the backup level to the main level.

11. The method of claim 8 , further comprising:

periodically generating a switching signal that operates a switching element; and

reducing a period of the generating the switching signal in response to determining that the auxiliary power supply is in the slow charging state.

12. The method of claim 8 , further comprising monitoring the voltage level that is charged to the auxiliary power supply by the first current source for the reference time amount to compare the voltage level that is charged to the auxiliary power supply by the first current source for the reference time amount with the reference voltage level.

13. A storage device, comprising:

a memory device including a plurality of memory blocks for storing data;

a memory controller configured to control the memory device; and

an auxiliary power supply including:

an auxiliary power storage configured to store auxiliary power that can be supplied in case supply of power to the memory device and the memory controller is abruptly stopped; and

a control circuit configured to:

determine a peak current level of the auxiliary power storage as a main level;

charge, for a reference time amount after the power is input to the auxiliary power supply, the auxiliary power storage by a first current source having the main level;

determine, after the reference time amount, that the auxiliary power supply is in a slow charging state when a voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount is lower than a reference voltage level;

change, in response to determining that the auxiliary power supply is in the slow charging state, the peak current level from the main level to a backup level that is greater than the main level; and

charge the auxiliary power storage by a second current source having the backup level.

14. The storage device of claim 13 , wherein the control circuit changes, in response to determining that the auxiliary power supply is in the slow charging state, the peak current level from the main level to the backup level when a charge limit time amount elapses after the power is input to the auxiliary power supply.

15. The storage device of claim 13 , wherein the auxiliary power storage includes a polymer capacitor.

16. The storage device of claim 13 , wherein the control circuit is further configured to change, when the voltage level that is charged to the auxiliary power storage by the second current source reaches a target voltage level, the peak current level from the backup level to the main level.

17. The storage device of claim 13 , wherein the control circuit is further configured to:

periodically generate a switching signal that operates a switching element, and

reduce, in response to determining that the auxiliary power supply is in the slow charging state, a period of the generating the switching signal.

18. The storage device of claim 13 , wherein the control circuit includes a voltage monitoring component configured to:

monitor the voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount, and

compare the voltage level that is charged to the auxiliary power storage by the first current source for the reference time amount with the reference voltage level.

19. The storage device of claim 13 , wherein the control circuit includes a counter that calculates the reference time amount.