Wireless power transmitter

1. A wireless power transmitter for receiving external power from a power adaptor, the wireless power transmitter comprising:

an output control signal generator configured to generate an output control signal by performing a step-down operation on the external power, and supply the output control signal to the power adaptor; and

a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver from the external power received from the power adaptor controlled by the output control signal, and wirelessly transmit the generated power to the wireless power receiver.

2. The wireless power transmitter of claim 1 , wherein:

the external power comprises first direct current (DC) power and second DC power having a voltage higher than a voltage of the first DC power; and

the performing of the step-down operation on the external power comprises performing the step-down operation on the first DC power.

3. A wireless power transmitter for receiving external power from a power adaptor, the wireless power transmitter comprising:

an output control signal generator configured to generate an output control signal using the external power, and supply the output control signal to the power adaptor; and

a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver from the external power received from the power adaptor controlled by the output control signal, and wirelessly transmit the generated power to the wireless power receiver,

wherein the output control signal comprises:

a first output control signal; and

a second output control signal having a voltage lower than a voltage of the first output control signal.

4. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first low-dropout (LDO) regulator configured to convert the external power into the first output control signal; and

a second LDO regulator configured to convert the external power into the second output control signal.

5. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

an LDO regulator configured to convert the external power into the first output control signal; and

two or more resistor elements configured to divide the first output control signal and output the divided first output control signal as the second output control signal.

6. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first LDO regulator configured to convert the external power into the first output control signal; and

a second LDO regulator configured to convert the first output control signal into the second output control signal.

7. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first DC/DC converter configured to convert the external power into the first output control signal; and

a second DC/DC converter configured to convert the external power into the second output control signal.

8. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a DC/DC converter configured to convert the external power into the first output control signal; and

two or more resistor elements configured to divide the first output control signal and output the divided first output control signal as the second output control signal.

9. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first linear regulator configured to convert the external power into the first output control signal; and

a second linear regulator configured to convert the external power into the second output control signal.

10. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first linear regulator configured to convert the external power into the first output control signal; and

a second linear regulator configured to convert the first output control signal into the second output control signal.

11. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first linear regulator configured to convert the external power into the first output control signal; and

two or more resistor elements configured to divide the first output control signal and output the divided first output control signal as the second output control signal.

12. The wireless power transmitter of claim 3 , wherein the output control signal generator comprises:

a first Zener regulator connected in series between a terminal to which the external power is input and a ground terminal, and configured to output the first output control signal from the external power; and

a second Zener regulator connected in series between the terminal to which the external power is input and the ground terminal, and configured to output the second output control signal from the external power; and

each of the first and second Zener regulators comprises a resistor element and a Zener diode connected to each other in series.

13. The wireless power transmitter of claim 3 , further wherein the output control signal generator is configured to generate the output control signal by performing a step-down operation on the external power.

14. The wireless power transmitter of claim 13 , wherein:

the external power comprises first direct current (DC) power and second DC power having a voltage higher than a voltage of the first DC power; and

the performing of the step-down operation on the external power comprises performing the step-down operation on the first DC power.

15. A wireless power transmitter for receiving, from a power adaptor, first direct current (DC) power or second DC power having a voltage higher than a voltage of the first DC power, the wireless power transmitter comprising:

an output control signal generator configured to generate an output control signal by performing a step-down operation on the first DC power, and supply the output control signal to the power adaptor; and

a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver from the first DC power or the second DC power received from the power adaptor controlled by the output control signal, and wirelessly transmit the generated power to the wireless power receiver.

16. The wireless power transmitter of claim 15 , wherein the wireless power generator comprises:

a converter configured to convert the first DC power or the second DC power into driving power;

an inverter configured to convert the driving power into alternating current (AC) power to be wirelessly transmitted to the wireless power receiver; and

a controller configured to control the converter and the inverter.

17. The wireless power transmitter of claim 16 , wherein the controller is further configured to variably control an output of the inverter depending on a magnitude of the DC power received from the power adaptor.

18. The wireless power transmitter of claim 16 , wherein the converter comprises a switching element; and

the controller is further configured to increase a duty ratio of the switching element of the converter in response to the first DC power being received from the power adaptor, and decrease a duty ratio of the switching element of the converter in response to the second DC power being received from the power adaptor.

19. A wireless power transmitter comprising:

an output control signal generator configured to receive external power from a power adaptor, generate an output control signal to control the power adaptor to change the external power, and supply the output control signal to the power adaptor, the power adaptor being configured to change the external power in response to the output control signal; and

a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver from the external power received from the power adaptor controlled by the output control signal, and wirelessly transmit the generated power to the wireless power receiver,

wherein the power adaptor is further configured to output first external power in response to the output control signal being in a first state, and output second external power having a different magnitude than the first external power in response to the output control signal being in a second state.

20. The wireless power transmitter of claim 19 , wherein the power adaptor is further configured to output the first external power in the absence of the output control signal, and output the second external power having a different magnitude than the first external power in response to the presence of the output control signal.

21. A wireless power transmitter comprising:

an output control signal generator configured to receive external power from a power adaptor, generate an output control signal to control the power adaptor to change the external power, and supply the output control signal to the power adaptor, the power adaptor being configured to change the external power in response to the output control signal; and

a wireless power generator configured to generate power to be wirelessly transmitted to a wireless power receiver from the external power received from the power adaptor controlled by the output control signal, and wirelessly transmit the generated power to the wireless power receiver,

wherein the external power is direct current (DC) power;

wherein the wireless power generator is further configured to convert the DC power into alternating current (AC) power to be wirelessly transmitted to the wireless power receiver; and

wherein the wireless power generator comprises a controller configured to control a magnitude of the AC power.

22. The wireless power transmitter of claim 21 , further comprising a voltage input determiner configured to receive the external power, generate a constant DC voltage from the external power, and supply the constant DC voltage to the controller to provide the controller with operating power.

23. The wireless power transmitter of claim 21 , wherein the power adaptor is further configured to output first external power in response to the output control signal being in a first state, and output second external power having a different magnitude than the first external power in response to the output control signal being in a second state.