ACTIVE DRIVE CIRCUIT

• Main Authors: KIM, HAK SU, KWON, O GYEONG, NA, YEONG SEON
• Format: Patent
• Language: English; Korean
• Published: 15.09.2001
• Edition: 7
• Subjects: ADVERTISING; ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICESUSING STATIC MEANS TO PRESENT VARIABLE INFORMATION; CRYPTOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; DISPLAY; EDUCATION; FREQUENCY-CHANGING; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL LOGIC ELEMENTS; OPTICS; PHYSICS; SEALS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

PURPOSE: An active drive circuit is provided to improve the capacity of a display device by minimizing a declination of a threshold voltage of a drive transistor. CONSTITUTION: A capacitor(Cch) for storing charges is connected with a positive supply voltages(Vdd). The first and the second drive transistors(Q2,Q1) have mirror circuits to drive each cell by applying charges stored in the capacitor(Cch) to a display device(OEL). A static current source(10) controls a size of drive current of the first and the second drive transistors(Q2,Q1) by a data signal. The first and the second switching transistors(Q3,Q4) transfers a control current of the static current source(10) to the first and the second drive transistors(Q2,Q1) in order to store the positive capacitor(Cch) corresponding to a difference of the supply voltages(Vdd).