Korea Advanced Institute of Science and Technology

Jin-Yong Jeon

Sang-Kyung Kim

Yong-Joon Jeon

Gyu-Hyeong Cho

Gyu Hyeong Cho

Young-Suk Son

Gun-Ho Lee

Gun-ho Lee

Young-suk Son

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

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Daegu, South Korea

Jin-Yong Jeon