Abstract: A wireless charger has an electromagnetic shielding function to efficiently shield electromagnetic waves generated in a transmitting coil of the wireless charger. The wireless charger includes a transmitting coil generating a magnetic field by a high frequency signal. The wireless charger further includes at least two electromagnetic wave shielding filters located on the transmitting coil and shielding electromagnetic waves generated in the transmitting coil.

Abstract: A wireless charger has an electromagnetic shielding function to efficiently shield electromagnetic waves generated in a transmitting coil of the wireless charger. The wireless charger includes a transmitting coil generating a magnetic field by a high frequency signal. The wireless charger further includes at least two electromagnetic wave shielding filters located on the transmitting coil and shielding electromagnetic waves generated in the transmitting coil.

Abstract: A spread spectrum clock generator includes a plurality of delay cells, wherein each delay cell includes at least one delayer receiving an external clock signal and causing a predetermined propagation delay to the received clock signal, and a controller transmitting a control signal to the delayer to control the propagation delay of the delayer according to a state value of the control signal. With this configuration, the spread spectrum clock generator using a delayer can have a simple circuit configuration and effectively attenuate an EMI.

Abstract: A remote control system exclusively controls an apparatus even when a plurality of the same type of apparatuses systems are located in a given place. A user defined code is designated by the user with respect to a transmitter and a receiver of the remote control system. The transmitter generates a remote control signal that includes the user defined code and a scan code in response to a control key input. The counterpart receiver responds to the coded signal received from the transmitter only when the user defined code received is identical with the one set in the receiver. The method of setting a user defined code in the transmitter includes the steps of determining whether a key input corresponds to the user defined code setting key designated in the key pad of the transmitter, setting a user defined code in response to another key input by the user, and storing the user defined code set by the user in a memory installed in the transmitter.

Abstract: A spread spectrum clock generator includes a plurality of delay cells, wherein each delay cell includes at least one delayer receiving an external clock signal and causing a predetermined propagation delay to the received clock signal, and a controller transmitting a control signal to the delayer to control the propagation delay of the delayer according to a state value of the control signal. With this configuration, the spread spectrum clock generator using a delayer can have a simple circuit configuration and effectively attenuate an EMI.

Abstract: In a system such as a computer system, and in a power controlling method for the system, power applied to the overall system is controlled according to correctness or incorrectness of a password in starting up the system. The password is received from a user. Power is applied to the overall system only when the input password is identical to a preset password, and the power is shut off if not. If the password is correct, the applied power is automatically shut off, thereby prohibiting unauthorized use of the system. In starting up the system, only the minimum power necessary for inputting the password and controlling the power is applied to the system, thereby advantageously preventing unnecessary power consumption.