APPARATUS FOR PROVIDING OPTIMUM ON-OFF CONTRAST RATIO AND MANUFACTURING METHOD THEREOF

摘要

PURPOSE: An apparatus for providing optimum on-off contrast ratio and a manufacturing method thereof are provided to optimize an on-off contrast ratio by monitoring a liquid crystal capacitor in a liquid crystal display and controlling a temperature of the liquid crystal display. CONSTITUTION: A voltage divider is formed by a temperature compensating circuit(102)having a fixing capacitor(108) and a temperature sensing capacitor(105) for sensing a change of a capacitor(CLC). A differentiators(110) has an operation amplifier(OA1), a resistor(R0) and a capacitor(C0). A continuous peak detecting unit(120) has MOS transistor units(M1-M4), a resistor unit(RS/H,RF) and a capacitor unit(CS/H,CF) for performing a peak voltage detecting function. A difference amplifying unit(125) has a difference amplifier(OA3) for comparing a voluntary setting voltage(VREF) with the voltage(VS/H). A heat corresponding to a predetermined reference temperature(T0) composition element unit(140) has an output buffer unit(130) and a heat resistor(RHEAT).