Korea Advanced Institute of Science and Technology

Samsung Electronics Co., Ltd.

Korea Institute of Energy Research

Sang-Kyung Kim

Gyu-Hyeong Cho

Young-Suk Son

Hee-Seok Han

Jin-Yong Jeon

Yong-Joon Jeon

Gyu Hyeong Cho

Chang Soo Lee

Gun-Ho Lee

Dong-Hyun Peck

Byung-Rok Lee

Gun-ho Lee

Chang-Hee Kim

Min-Chul Lee

Young-suk Son

Won-Chul Cho

Ki-Don Nam

Seong-Yop Lim

Doo-Hwan Jung

Jae Hun Lee

Sechan Lee

The present invention relates to a method for producing porous carbon materials comprising the following steps: (S1) forming carbon coatings on surfaces of ceramic nanoparticles; (S2) mixing carbon precursors and ceramic nanoparticles on which carbon coatings are formed in the step (S1); (S3) heat-treating the mixture of the ceramic nanoparticles having carbon coatings thereon and carbon precursors, prepared in the step (S2) to carbonize the mixture; and (S4) removing the ceramic nanoparticles from the material obtained in the step (S3). The method for producing porous carbon materials according to the present invention enables porous carbon materials in which mesopores are uniformly distributed, to be mass produced with low costs. The porous carbon materials having mesopores may be used as catalyst supports for fuel cells, and thus may be used in producing electrodes for fuel cells.

Method for producing porous carbon materials having mesopores and catalyst support for a fuel cell produced using same

Disclosed herein is an Active Matrix Organic Light-Emitting-Diode (AMOLED) drive circuit using transient current feedback. The AMOLED drive circuit includes a current Digital-to-Analog Converter (DAC), a data line drive transistor, a constant current source, a variable current source, a differential amplifier, and a transient charging current control unit. The DAC generates current corresponding to input digital data. The data line drive transistor is configured such that the drain terminal thereof is connected to the output node of the current DAC. The constant current source is connected between the source terminal of the data line drive transistor and a ground. The variable current source is connected between both the output node of the current DAC and the drain terminal of the drive transistor, and a voltage source. The differential amplifier is configured to input the output voltage thereof to the gate terminal of the drive transistor. The transient charging current control unit is configured to increase or decrease the bias current of the variable current source depending on variation in the voltage of the output node of the current DAC.

AMOLED drive circuit using transient current feedback and active matrix driving method using the same

A current feedback-type AMOLED driving circuit. The current feedback-type AMOLED driving circuit includes a plurality of pixel circuits each having a data terminal for receiving a pixel current command, and a sense terminal for transmitting pixel current to a driver Integrated Circuit (IC), and a plurality of data lines provided such that a single data line is provided for a single column formed by a plurality of pixel circuits, thus data terminals of the pixel circuits, forming the column, are connected to the data line. In the AMOLED driving circuit, two columns are paired, sense terminals of pixel circuits, forming a first column of the two columns, are connected to a data line for a second column, and sense terminals of pixel circuits, forming the second column, are connected to the data line for the first column. The AMOLED driving circuit is operated such that, when the first column is driven, the data line for the second column is used as a current feedback line for the first column, and when the second column is driven, the data line for the first column is used as a current feedback line for the second column. Accordingly, the number of pads of the driver IC is limited to one per column, and price competitiveness of the driver IC is improved.

Current feedback-type AMOLED where sense feedback is sent over the adjacent data line

Disclosed herein are a pixel circuit and driving method for active matrix Organic Light-emitting Diodes (OLEDs), and a display using the same. The pixel circuit includes a Voltage Control Current Source (VCCS), a high gain amplifier, a storage capacitor, and first and second switches. The VCCS is configured to drive OLEDs. The high gain amplifier is configured such that the control input signal of the VCCS causes the VCCS to be placed in an ON or OFF state. The storage capacitor is located between the input terminal of the high gain amplifier and a data line so as to assign the ON-time of the VCCS. The first and second switches are configured to be controlled through a scan line so as to store voltage in the storage capacitor and control the light-emitting time of the OLEDs, and are formed the input terminal of the high gain amplifier and the input terminal of the VCCS, respectively.

Pixel circuit and driving method for active matrix organic light-emitting diodes, and display using the same

Disclosed herein is a driving method and circuit for the automatic voltage output of an active matrix organic light emitting device, which is capable of resolving the non-uniformity of brightness between pixels. The circuit of the present invention includes timing generation means for generating a data drive start signal; sweep voltage generation means for generating a sweep voltage signal in response to output of the timing generation means; current level detection means for sensing an amount of current, which flows into pixels, based on output of the sweep voltage generation means, and outputting a sensing result to a data line; comparison means for comparing output of the current level detection means with a reference signal that determines stop timing for data writing, and outputting a comparison result; and data writing start/end control signal generation means for starting to operate in response to the output of the timing generation means, and generating data writing start and end control signals to a program stop line of a display panel. The invention can shorten data writing time and improve the precision of data writing. Furthermore, the present invention can simplify a data drive circuit and achieve the uniformity of brightness between pixels.

Driving method and circuit for automatic voltage output of active matrix organic light emitting device and data drive circuit using the same

A discharge lamp driving circuit includes an inverter, a ballast capacitor, a discharge lamp, and a lamp current detecting circuit. The inverter converts a DC voltage into an AC voltage with high frequency to output the AC voltage to an output port based on a pulse width modulation control signal. The lamp current detecting circuit outputs a first voltage signal and a second voltage signal according to a voltage across the ballast capacitor to generate a lamp current sensing voltage that is proportional to a lamp current flowing through the discharge lamp. The pulse width modulation control signal has a width varying with amplitude of the lamp current so that the lamp current may be accurately detected.

Discharge lamp driving circuit and method of driving a discharge lamp

Discharge lamp driving circuit having a signal detection circuit therein

Disclosed herein are a time division sampling digital to analog converter for a flat panel display, a method of implementing the digital to analog converter, and a data driver circuit using the digital to analog converter. The time division sampling digital to analog converter includes a timing signal generation means for generating timing signals, a data selection means for receiving n-bit digital data, dividing the n-bit digital data into k groups, and outputting the divided digital input data; k reference signal generation means for each outputting 2analog reference signals; a reference signal selection means for receiving the outputs of the reference signal generation means and outputting only 2analog reference signals selected according to a timing signal from the timing signal generation means; a multiplexer for outputting one of reference signals from the reference signal selection means using the n/k-bit digital data from the data selection means as a control input; and a sampling mode analog addition means for sampling and storing the output of the multiplexer according to a timing signal from the timing signal generation means.

Time division sampling digital to analog converter for driving flat panel display, method of implementing the same, and data driver circuit using the same

Disclosed herein is a divide-add circuit and a high-resolution Digital-to-Analog Converter (DAC) using the same. The DAC includes a plurality of DAC units and one or more divide-add circuit units. The plurality of DAC units performs Digital-Analog (DA) conversion on two or more segmented codes, into which an input digital code is segmented. The one or more divide-add circuit units is configured to be each composed only of capacitors and switches and to generate a final DA conversion output for the entire input digital code based on the voltages of the DAC units. Accordingly, a high resolution of more than ten bits can be implemented.

Divide-add circuit and high-resolution digital-to-analog converter using the same

Discharge lamp driving circuit

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Daejeon, South Korea

Sang-Kyung Kim