Abstract: A radio frequency identification tag, used in a radio frequency identification system, includes an antenna unit for receiving an external magnetic wave to generate an induced current; a driving voltage generating unit for converting the induced current into a constant voltage and outputting the constant voltage; and a state detecting unit for detecting information about a change in an operational state of the driving voltage generating unit. The tag further includes a memory for storing temperature data corresponding to the information about the change in the operational state and data needed for identification; and a controlling unit for reading out, from the memory, the temperature data dependent on the information about the change in the operational state detected by the state detecting unit and the identification data. The read temperature and identification data are transmitted via an antenna unit.

Abstract: A radio frequency identification (RFID) tag capable of improving convenience of a user and a method of driving the RFID tag are provided. The RFID tag includes a displaying unit displaying tag data indicating a current state of the RFID tag. The displaying unit displays the tag data even when the RFID tag does not exist in a read range of the RFID reader. Thus, a user can recognize the current state of the RFID tag without using the RFID reader.

Abstract: An RFID tag capable of enhancing the reliability of products and an RFID system having the same are provided. The RFID tag includes a tag antenna receiving waves from an RFID reader, and a tag driver. The tag driver includes an accumulation mode capacitor adjusting a capacitance value corresponding to an input voltage. That is, the tag driver adjusts the amplitude of a modulated carrier wave using the accumulation mode capacitor. Accordingly, the RFID tag adjusts the impedance of the tag driver without adjusting the current transmitted from the tag driver. Therefore, impedance adjustment of the tag driver can prevent the voltage transmitted from the tag driver from being lower than the reference voltage, and modulation and demodulation can be stably performed. As a result, the reliability of products can be enhanced.

Abstract: Provided are an RFID tag capable of limiting an over-voltage and a method for controlling an over-voltage thereof. The RFID tag includes: an antenna unit receiving external electromagnetic waves to induce an input voltage; a voltage generator rectifying the input voltage to generate a driving voltage; a voltage limiter adaptively turned on and/or off depending on whether the input voltage is high or low to limit an intensity of the input voltage input into the voltage generator; and a logic controller controlling the antenna unit to generate authentication information based on the driving voltage and transmit the authentication information.

Abstract: Provided are a method and apparatus for bonding an element, which has a transparency with respect to UV light, to a substrate. The method includes forming an aluminum layer on a surface of the substrate, disposing the element on the aluminum layer, and bonding the element to the aluminum layer by applying pressure on the element toward the aluminum layer and irradiating UV light on a bonding area between the element and the aluminum layer. The apparatus includes a holder, a pressurizing plate installed at the bottom of the holder to apply pressure on the element toward the substrate and formed of a material having a transparency to UV light, a UV light lamp which is installed in the inner space of the holder, and a collimating lens which is positioned between the UV light lamp and the pressurizing plate and collimates UV light emitted from the UV light lamp.

Abstract: An optical coupling device for coupling light to a core of an optical waveguide device. The optical coupling device is connected to the core of the optical waveguide device at a first end and convex at a second end opposite the first. The optical coupling device includes a waveguide connecting the first and second ends of the optical coupling device, for light transmission, and a cladding surrounding the waveguide.

Abstract: In a radio frequency identification (RF-ID) system and method of sending additional signals, the radio frequency identification (RF-ID) system includes a tag portion including a sensor, the tag portion for outputting a composite signal including additional data from the sensor and basic data necessary for certification, an antenna for receiving the composite signal output from the tag portion, and a RF-ID reader portion for retrieving the composite signal received from the antenna and for decoding the basic data and the additional data.

Abstract: An over-voltage protection circuit (i.e., a limiter), includes: a first switching block having a plurality of semiconductor elements, serially connected to each other and turned on in sequence according to the magnitude of an input voltage; and a plurality of second switching blocks, in which each of the second switching blocks includes a pair of serially connected semiconductor elements having different current properties. The second switching blocks are connected in parallel to the first switching block. By minimizing a leakage current when an input voltage is below a reference voltage and by maximizing a leakage current when the input voltage is above the reference voltage, the limiter prevents excessive current from flowing into the RF tag circuit when the input voltage is below the reference voltage, and ensures that a sufficient amount of current is supplied to a regulator when the input voltage is below the reference voltage.

Abstract: An ultra low power oscillator includes a current supply unit converting current supplied from an external bias power source into first and second low currents of predetermined amounts, and an oscillation unit oscillating and creating a predetermined frequency signal if the first and second low currents are supplied from the current supply unit. The oscillation unit includes a plurality of inverters connected in series, and the current supply unit includes a current limit circuit composed of NMOS and PMOS transistors connected to the respective inverters. The current flowing when the transistors in the respective inverters are simultaneously turned on is limited, and thus the power consumption can be reduced.

Abstract: A radio frequency identification reader and a radio frequency identification tag that use an ultrahigh frequency band, and action methods of the radio frequency identification reader and the radio frequency identification tag. The radio frequency identification reader includes: a data generator generating data to be transmitted to a radio frequency identification tag; if a command to control the radio frequency identification tag has to be authenticated, a reader controller controlling the data generator to generate the data including an authentication code; and a reader transmitter transmitting the data to the radio frequency identification tag. As a result, securing of communications of a specific command between the radio frequency identification reader and the radio frequency identification tag can be reinforced.

Abstract: A reference voltage generating circuit with ultra-low power consumption, which includes: a constant current circuit part generating a first constant current from a supply voltage; a current mirror circuit part mirroring the constant current and supplying a second constant current; a voltage control circuit part receiving the second constant current and generating a first reference voltage by using substrate transistors driven by a PTAT (Proportional To Absolute Temperature) voltage and MOS transistors driven by a CTAT (Complementary To Absolute Temperature) voltage; and an output circuit part amplifying an output voltage from the voltage control circuit part to generate second to fourth reference voltages, and feeding back at least one of the second to fourth reference voltages to the voltage control circuit part so that the magnitude of an output voltage is adjusted.

Abstract: A low leakage Schottky diode and fabrication method thereof. The Schottky diode includes a n-type semiconductor; an anode having a circular periphery formed in a region above the n-type semiconductor; and a cathode formed in a region above the n-type semiconductor and having a pattern surrounding and set apart from the outer periphery of the anode. Because there are no edges at the anode and cathode interface, leakage current is minimized.

Abstract: Disclosed is a rectifier for supplying double voltage and an RFID tag thereof. The rectifier includes a charging part for charging an input voltage induced to input ends by a received radio frequency (RF) signal; a power provider for charging a sum voltage corresponding to the sum of the input voltage induced to the input end and the voltage charged in the charging part as a power voltage, and discharging the charged power voltage to provide a direct current (DC) power; and a switching part for switching to supply the input voltage induced at the input ends to the charging part during a first interval and switching to supply the sum voltage to the power provider during a second interval. Accordingly, double voltage can be supplied to other electric elements formed in the RFID tag and overcurrent caused by overvoltage can be prevented from flowing into the elements.

Abstract: A voltage transform circuit transforms a transferred voltage to a desired magnitude of voltage. The voltage transform circuit includes: a first power supply unit for providing a digital voltage (Vdd-1) of a first magnitude; a second power supply unit for providing an analog voltage (Vaa-2) of a second magnitude; and a voltage transform unit formed with a plurality of MOS transistors, wherein the MOS transistors operate to transfer the digital voltage (Vdd-1) from the first power supply unit, and output a digital voltage (Vdd-3) of a third magnitude corresponding to the analog voltage (Vaa-2) transferred from the second power supply unit. By using an analog voltage (Vaa-2) that is higher than the digital voltage (Vdd-1), it becomes possible to increase the magnitude of the output digital voltage (Vdd-3). By supplying this high digital voltage (Vdd-3) to a charge pump, the level of the charge pump is lowered.

Abstract: A semiconductor device using schottky diodes for removing noise, a fabrication method, and an electrostatic discharge prevention device are provided. The semiconductor device includes a P-well substrate; insulation layers deposited on etched regions of the substrate; an N-well layer deposited on an etched region of the P-well substrate between the insulation layers; P+ type implants injected to a first region and a second region of the N-well layer; and first and second metals formed in schottky contact on the first and second regions, respectively. The method includes etching away regions of a P-well substrate and depositing an insulation substance; etching away the P-well substrate and depositing the insulation substance between the insulation layers to create an N-well layer; injecting P+ type implants to a first region and a second region of the N-well layer; and forming first and second metals in schottky contact on the first and second regions, respectively.

Abstract: A surface mounted device (SMD) package using coaxial cables and a method of manufacturing the SMD by forming green sheets and selecting portions for mounting the coaxial cables on the green sheets and forming holes in the portions selected, stacking and heating the green sheets having the holes, and inserting the coaxial cables into the holes of the green sheets. The SMD includes a device mounting unit formed in the package for mounting a high frequency electronic device which transmits and receives high frequency signals, transmission lines electrically connected to the high frequency electronic device, and the coaxial cables penetrating internal and external portions of the package and including internal lead wires which contact the transmission lines. The SMD package is formed to conveniently transfer high frequency signals without the signal transfer loss.

Abstract: A digital temperature sensor and a system and a method for measuring a temperature are provided. The system includes a reference signal generator including one or more resistance elements; a temperature sensor including a plurality of discrete resistance elements arranged parallel with one another; a multiplexer multiplexing the plurality of discrete resistance elements and the reference resistance element so that the plurality of discrete resistance elements sequentially distribute a power voltage together with the reference resistance element; a comparator having the voltages distributed by the reference resistance element and a discrete resistance element selected by the multiplexer; and a counter counting sequential switchings of the multiplexer.

Abstract: A compression bonding method includes patterning a metal bonding film in predetermined shapes on a substrate; and disposing a bonded element above the metal bonding film and applying heat to the substrate and pressure to the bonded element, thereby bonding the bonded element to the substrate having the metal bonding film. Since the compression bonding method allows bonded elements having various shapes and sizes to be bonded to a substrate at a low temperature and pressure, manufacturing is simplified, and the compression bonding method can be applied to various sealing and packaging processes.

Abstract: Disclosed are a temperature measurement apparatus and method for measuring temperature by using RF signals having different frequencies. The temperature measurement apparatus includes a parameter generation unit for generating a first parameter based on a radio frequency (RF) signal having a first frequency and a second parameter based on an RF signal having a second frequency; a parameter detection unit for detecting the generated first and second parameters; and a control unit for calculating a temperature value based on the detected first and second parameters. Accordingly, the temperature measurement apparatus can measure temperature by use of existing components and received RF signals without any addition of a temperature sensor, as well as measure temperature precisely without having any influence on the intensities of RF signals that can vary due to the changes of transmission distances and signal-receiving environments.

Abstract: A radio frequency identification tag, used in a radio frequency identification system, includes an antenna unit for receiving an external magnetic wave to generate an induced current; a driving voltage generating unit for converting the induced current into a constant voltage and outputting the constant voltage; and a state detecting unit for detecting information about a change in an operational state of the driving voltage generating unit. The tag further includes a memory for storing temperature data corresponding to the information about the change in the operational state and data needed for identification; and a controlling unit for reading out, from the memory, the temperature data dependent on the information about the change in the operational state detected by the state detecting unit and the identification data. The read temperature and identification data are transmitted via an antenna unit.