Abstract: A power amplifier, a power amplifier system, and an operating method thereof are provided. The power amplifier system may include a power amplifier, a power amplifier controller, and a voltage generator. The power amplifier may include a plurality of power transistor cells each of which receives an RF signal through a control terminal thereof to amplify the RF signal. The power amplifier controller may control turn-on and turn-off operations of at least one power transistor cell among the plurality of power transistor cells based on a power mode. The voltage generator may generate a power supply voltage supplied to first terminals of the power transistor cells and may change the power supply voltage depending on the power mode.

Abstract: An iris scanning camera module includes a housing having an internal space, and a first lens module and a second lens module inside the internal space. The first lens module and the second lens module have optical axes parallel to each other. An image sensor is configured to convert light passing through the first lens module and the second lens module into an image. The image sensor is divided into a region including a color pixel array and as another region including a black-and-white pixel array. The color pixel array is aligned in an optical axis direction of the first lens module, and the black-and-white pixel array is aligned in an optical axis direction of the second lens module.

Abstract: There are provided a hydrodynamic bearing assembly and a manufacturing method thereof. The hydrodynamic bearing assembly includes: an oil sealing part formed between a fixed member and a rotating member; and a silicon containing diamond-like-carbon (Si-DLC) or tungsten carbide (W-Carbide) coating layer formed on at least one surface of the fixed member and the rotating member. The silicon containing diamond-like-carbon (Si-DLC) or tungsten carbide (W-Carbide) coating layer is formed on the at least one surface of the fixed member and the rotating member, whereby abrasion of the fixed member and the rotating member due to friction therebetween may be prevented.

Abstract: Disclosed herein is a spindle motor including: a shaft insertedly mounted so as to be perpendicular to an upper side portion; a sleeve receiving the shaft therein to thereby rotatably support the shaft and forming a space between the sleeve and the shaft to thereby be spaced apart from the shaft so as not to contact the shaft; a holder having the sleeve mounted in an inner portion thereof and having a lower portion mounted on an upper portion of a plate; and the plate integrally supporting lower portions of the shaft and the sleeve and including connecting parts connecting the holder and the plate to each other and fixing parts fixing positions of the holder and the plate so that a lower surface of the holder is coupled thereto.

Abstract: Provided is a low-power ZigBee device provided with a sleeping mode and an active mode including a power supplying unit for supplying a power; a Medium Access Control (MAC) processing unit for receiving a wake-up packet and for controlling a modem unit and an Radio Frequency (RF) unit; and a Central Processing Unit (CPU) for receiving and processing a data packet, wherein the MAC processing unit makes the power supplying unit apply a power to the CPU based on a result of checking an identification (ID) of the wake-up packet.

Abstract: The present invention provides a color electronic paper display device, which includes: a base; a first colorant disposed on the base; a second colorant disposed on the base, the second colorant having lower reflectance and size lower than those of the first colorant; and an electrode part for applying voltages to the first and second colorants.

Abstract: There is provided a method of manufacturing a back-surface electrode type solar cell. The method may include: forming a conductive metal thin film on a crystalline silicon wafer; forming plate-resistant partition walls on a top surface of the conductive metal thin film; forming a metal layer in a space between the plate-resistant partition walls and then removing the plate-resistant partition walls; and removing the conductive metal thin film that is exposed by removing the plate-resistant partition walls so as to expose the crystalline silicon wafer.

Abstract: There is provided a method of manufacturing a non-shrinkage ceramic substrate, and a non-shrinkage ceramic substrate using the same.

Abstract: There is provided a frequency synthesizer including a multi-band voltage controlled oscillator having a plurality of voltage controlled oscillating cores outputting oscillation frequencies having different bands according to an input control voltage. Each of the voltage controlled oscillating cores outputs a frequency band divided into a plurality of bands, and the voltage controlled oscillating core operates by each of the divided bands, and one of the voltage controlled oscillating cores operates in one of the bands according to the control voltage. The frequency synthesizer further includes a comparator unit and an oscillation band-determining unit. The comparator unit compares the control voltage with a pre-set reference voltage range. The oscillation band-determining unit changes the band where the voltage controlled oscillating core operates into another one of the bands when the control voltage is out of the pre-set reference voltage range.