Dongbu Hitek Co., Ltd.

Samsung Display Co., Ltd.

Solum Co., Ltd.

Hwan Hee Cho

Sung-Hoon Bea

Sung Wook Kim

Dong Hyun Kim

Jung Chul Gong

Tsuyoshi Naijo

Sung-Soo Bae

Dae Yup Shin

Myeong Suk Kim

Seul Ong Kim

Ho Joon Jang

Hye In Jeong

An organic light emitting device includes: a first electrode; a second electrode that overlaps the first electrode; and an organic layer that is disposed between the first electrode and the second electrode, wherein the organic layer comprises a hole transport region that includes a hole transport material and a p-dopant, and wherein when a doping amount of the p-dopant doped to the hole transport region exceeds 1 wt %, the following Equation 1 is satisfied, while when the doping amount of the p-dopant is 1 wt % or less than 1 wt %, the following Equation 2 is satisfied:HOMO_HTM&#x2212;LUMO_-dopant&#x3c;&#x2212;0.05 eV&#x2003;&#x2003;[Equation 1]HOMO_HTM&#x2212;LUMO_-dopant&#x3e;&#x2212;0.05 eV&#x2003;&#x2003;[Equation 2]In Equation 1 and Equation 2, HOMO_HTM denotes HOMO energy of the hole transport material and LUMO_p-dopant denotes LUMO energy of the p-dopant.

Organic light emitting device and display device including the same

An organic light emitting display element according to an example embodiment includes: a first electrode, an emission layer positioned on the first electrode, and a second electrode positioned on the emission layer, in which the emission layer includes at least one of the compounds represented by the following Chemical Formulas 1 to 3. 

Organic light emitting diode display

A power supply has a primary side and a secondary side electrically insulated from each other. A switching operation based on a switching of the primary side is controlled according to the power transmitted to the secondary side, and the switching operation is converted at a time earlier than a switching conversion time of the primary side by a predetermined time.

Control device of synchronous rectifier and power supply

A power supply apparatus and method for an active matrix organic light emitting diode (AMOLED) is disclosed. The power supply apparatus supplies power to the AMOLED while using a switching frequency varied in accordance with a clock signal, and includes a load checker for comparing a load current of the AMOLED with a first reference voltage, and outputs a result of the comparison as a load check signal, and a frequency oscillator for generating the clock signal which has a variable frequency in response to the load check signal. The power supply apparatus is switched in accordance with a clock signal having a frequency modulated based on a load condition of the AMOLED, for example, a load current. Accordingly, it is possible to reduce switching power loss caused by unnecessary power consumption under the condition that a small load current is generated, thereby achieving an enhancement in efficiency.

Power supply apparatus and method for AMOLED

A voltage regulator uses a comparing apparatus having hysteresis characteristics. The voltage regulator includes a comparator for comparing a comparison voltage with a reference voltage, and outputs a result of the comparison; a switching controller for generating a plurality of switching signals in response to the comparison result; resistors connected in the form of a string, to divide the comparison voltage into a plurality of voltages; and a switching box for selecting one of the plural voltages, as the comparison voltage, in response to the switching signals.

Current mode DC-DC converter having a pulse width modulation signal of reduced delay

A slope compensation circuit includes an oscillator for generating a first clock signal having a reference frequency, a ramp signal generator for generating a ramp signal having a duty ratio of about 50% or higher based on the first clock signal, and a slope compensation signal generator for outputting a slope compensation current based on the ramp signal.

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Goyang-si, South Korea

Hwan Hee Cho