Abstract: There is provided a low drop-out regulator. The low drop-out regulator includes an amplifier including an odd number of operational amplifiers connected to one another in series, and an output unit including a pass transistor operated by an output from the amplifier and generating an output voltage to be applied to a load, wherein the pass transistor is an N-channel transistor, and the amplifier controls a feedback loop gain between an output terminal of one of the odd number of operational amplifiers and the output unit. The feedback loop gain may be controlled independently from the trans-conductance of the pass transistor, whereby the stable output voltage may be generated, even in the case that the load and the input voltage are changed, and the design parameter may be simplified.

Abstract: Disclosed herein is a charging apparatus using a pad type electrode contact point, the charging apparatus including: a charging plate having a plate shape; and an attaching plate installed on a portable terminal to provide the power to a charging circuit of the portable terminal.

Abstract: The present invention discloses an impedance matching apparatus. The impedance matching apparatus includes: a multilayer printed circuit board; a signal line including a plurality of signal layers with the same pitch and formed by sequentially arranging the plurality of signal layers on the multilayer printed circuit board; and a ground plane including a plurality of ground layers, wherein the plurality of ground layers are arranged to get closer to a bottom surface of the multilayer printed circuit board from a region corresponding to one side of the signal line to a region corresponding to the other side of the signal line. The impedance matching apparatus can implement a line width without any problem of a process yield by determining specific impedance by a distance between the signal layer and the ground layer formed in corresponding positions, thereby improving the process yield.

Abstract: Disclosed herein is a wireless power transmission system, including: a transmission unit generating and transmitting power for charging a battery; a reception unit receiving the transmitted power and charging the battery with power; and a transmission control unit detecting a charging status of the battery by using the transmitted power, and, if the charging status of the battery is in a damage section due to reflective power, controlling the transmission unit to transmit power lower than power of a normal operation, whereby damage of transmission and reception devices due to a reflective wave can be minimized.

Abstract: Disclosed is a wireless energy transmission structure which includes a disc part including a first conductor plate and a second conductor plate which are spaced to face each other and a dielectric material inserted between the first conductor plate and the second conductor plate, and generating an electric field between the first conductor plate and the second conductor plate; and a ring-shaped wire part one end of which is connected to the first conductor plate and the other end of which is connected to the second conductor plate, and having a meta structure in which a plurality of meta cells is repetitively arranged so as to induce a magnetic field using the electric field, so that the wireless energy transmission structure is reduced in size and is improved in transmission distance and transmission efficiency.

Abstract: Disclosed herein is a wireless energy transmission structure, which includes a printed circuit board, a disk section, and a wire section. The printed circuit board is formed in a ring type, the disk section is constituted by a first conductive plate and a second conductive plate formed on portions of the printed circuit board corresponding to each other to be spaced by a predetermined gap and a dielectric material inserted between the first conductive plate and the second conductive plate, and the wire section is constituted by a plurality of meta cells having a meta material structure, which are repetitively formed to surround the exterior and interior of the printed circuit board and a transmission line connected to each of the first conductive plate and the second conductive plate and surround the plurality of meta cells.

Abstract: Disclosed herein are an apparatus and a method for charging wireline and wireless powers. The apparatus for charging wireline and wireless powers includes: a main battery; an auxiliary battery; a wireline charging module providing wireline power to the main and auxiliary batteries; and a wireless charging module connected to the wireline charging module to thereby provide wireless power to the main and auxiliary batteries. Therefore, wireline charging and the wireless charging may be simultaneously performed, thereby making it possible to save a time required to charge power and to improve the convenience for users according to various charging scenarios using the wireline charging and the wireless charging.

Abstract: Disclosed are a wireless power transmitter capable of transmitting power wirelessly according to an impedance of an output side and a wireless power transceiver. There are provided a wireless power transmitter and a wireless power transceiver including: a wireless power transmitting unit converting input power into a preset transmission power and transmitting the converted input power wirelessly; and a controlling unit controlling a transmission of the transmission power according to a level of output impedance of the transmission power output from the wireless power transmitting unit.

Abstract: Disclosed herein is a wireless power transfer system. The wireless power transfer system includes a wireless power transmitter receiving power input from the outside to generate a wireless power signal to be transmitted in wireless and transmitting the generated wireless power signal in wireless by a magnetic resonance manner using an LC serial-parallel resonance circuit; a wireless power receiver installed in a charging device to receive the wireless power signal transmitted from the wireless power transmitter by the magnetic resonance manner using the LC serial-parallel resonance circuit and output the received wireless power signal; and a charging circuit installed in the charging device to allow the power output from the wireless power receiver to charge an embedded battery, thereby making it possible to efficiently provide power in wireless.

Abstract: In order to reduce a current mismatch by laying-out the bias circuit of current cells adjacent to each other in a common current centroid manner or connecting the output lines of the current cells in a tournament manner, there is provided a digital-analog converter in which a plurality of current cells are two dimensionally and symmetrically disposed according to a previously determined order, the digital-analog converter including: a first current cell group including a portion of the plurality of current cells; and a second current cell group including the rest of the plurality of current cells, not included in the first current cell group, the outputs of each current cell of the first current cell group being connected to the outputs of each current cell of the second current cell group in a tournament manner, wherein each of the plurality of current cells includes: a switch circuit switching the output and block of a unit current according to an input signal; and a bias circuit mirroring current supplied

Abstract: Disclosed herein is a wireless power transmission/reception apparatus. The wireless power transmission/reception apparatus includes a wireless power transmission unit configured to generate a wireless power signal to be transmitted, transmit the wireless power signal using magnetic resonance, receive a reflected wireless power signal from a wireless power reception unit, determine whether a load device is present, and transmit a wireless power signal if it is determined that the load device is present in such a way that impedance and output power depending on variation in a distance to the load device are automatically tracked, and wireless power is supplied to the load device in an optimized state. A wireless to power reception unit is connected to the load device, and configured to receive the wireless power signal, provide the wireless power signal to the load device, and reflect a reflected wireless power signal towards the wireless power transmission unit.

Abstract: Disclosed is a wireless communication apparatus having a self sensing function, which can detect an object by use of a wake-up function without employing a separate sensor. The wireless communication apparatus includes a communication unit wirelessly communicating with a server forming a wireless network, and a wake-up unit waking up the communication unit under the control of the server when the communication unit is in sleep mode, and sensing the presence of an object within a preset communication range according to a reflection signal, which is a signal reflected by the object after being transmitted from the communication unit.

Abstract: In a key scanning circuit, a key input unit has a parallel connection of a plurality of circuits having a series connection of resistors and switches between a power supply input terminal and a key scanning terminal. The resistors connected in parallel have different resistances. A current mirror has a first terminal connected to the key scanning terminal. A reference current source is connected between a second terminal of the current mirror and the power supply input terminal.

Abstract: Disclosed herein are a wireless power transmission apparatus and a transmission method thereof. The wireless power transmission apparatus is configured to include a wireless power transmitter generating a wireless power signal to be wireless transmitted, wirelessly transmitting the generated wireless power signal by a magnetic resonance manner, receiving a reflection wireless power signal to determine whether or not a load apparatus is presented, and supplying power to the load apparatus; and a wireless power receiver connected to the load apparatus and receiving the transmitted wireless power signal by the magnetic resonance manner and supplying it to the connected load apparatus and reflecting the remaining wireless power signal to the wireless power transmitter, whereby a transmission apparatus can recognize a receiving environment and resonance characteristics are improved, without a separate communication device or a system.

Abstract: Disclosed herein is a rectifier circuit of a wireless power transmission system, the rectifier circuit including: a rectifying unit rectifying an RF signal inputted through an RF input stage in a half-wave rectification type; an impedance matching unit installed between the RF input stage and the rectifying unit to match an impedance between the RF input stage and the rectifying unit; and a filtering unit filtering the signal rectified by the rectifying unit, thereby removing a radio frequency component and reducing a radio frequency ringing phenomenon, and thus, improving the efficiency of the rectifier circuit.

Abstract: Disclosed herein is an apparatus for transmitting and receiving wireless energy using meta-material structures having a zero refractive index. The apparatus includes a wireless energy transmission unit and a wireless energy reception unit. When external power is applied thereto, the wireless energy transmission unit generates wireless energy to be wirelessly transmitted, and then wirelessly transmits wireless energy, which is normally propagated radially when the generated wireless energy is transmitted, using a magnetic resonance method while concentrating the wireless energy in one direction.

Abstract: Disclosed herein is there is provided an apparatus for transmitting and receiving wireless energy using meta-material structures having a negative refractive index. The apparatus includes a wireless energy transmission unit and a wireless energy reception unit. The wireless energy transmission unit generates wireless energy to be wirelessly transmitted, and then wirelessly transmits wireless energy, which is normally propagated radially, using a magnetic resonance method while concentrating the wireless energy at a single point. The wireless energy reception unit wirelessly receives the wireless energy using the magnetic resonance method while concentrating the wireless energy at a single point.

Abstract: Disclosed herein is a wireless energy transmission structure, which includes a printed circuit board, a disk section, and a wire section. The printed circuit board is formed in a ring type, the disk section is constituted by a first conductive plate and a second conductive plate formed on portions of the printed circuit board corresponding to each other to be spaced by a predetermined gap and a dielectric material inserted between the first conductive plate and the second conductive plate, and the wire section is constituted by a plurality of meta cells having a meta material structure, which are repetitively formed to surround the exterior and interior of the printed circuit board and a transmission line connected to each of the first conductive plate and the second conductive plate and surround the plurality of meta cells.

Abstract: Disclosed is a wireless energy transmission structure which includes a disc part including a first conductor plate and a second conductor plate which are spaced to face each other and a dielectric material inserted between the first conductor plate and the second conductor plate, and generating an electric field between the first conductor plate and the second conductor plate; and a ring-shaped wire part one end of which is connected to the first conductor plate and the other end of which is connected to the second conductor plate, and having a meta structure in which a plurality of meta cells is repetitively arranged so as to induce a magnetic field using the electric field, so that the wireless energy transmission structure is reduced in size and is improved in transmission distance and transmission efficiency.

Abstract: In order to reduce a current mismatch by laying-out the bias circuit of current cells adjacent to each other in a common current centroid manner or connecting the output lines of the current cells in a tournament manner, there is provided a digital-analog converter in which a plurality of current cells are two dimensionally and symmetrically disposed according to a previously determined order, the digital-analog converter including: a first current cell group including a portion of the plurality of current cells; and a second current cell group including the rest of the plurality of current cells, not included in the first current cell group, the outputs of each current cell of the first current cell group being connected to the outputs of each current cell of the second current cell group in a tournament manner, wherein each of the plurality of current cells includes: a switch circuit switching the output and block of a unit current according to an input signal; and a bias circuit mirroring current supplied