Patent ID: 7893907

Claim:
A driving apparatus for a liquid crystal display, comprising: a liquid crystal display panel provided with a plurality of data lines; a brightness detector to detect a black brightness component and a white brightness component of data supplied to the plurality of data lines; a controller to compare magnitudes of a black brightness amount with a white brightness amount in the white and black brightness components detected by the brightness detector during one frame to generate a compared result and to control an application of a common voltage on a basis of a black brightness data level or a white brightness data level of data supplied to the plurality of data lines in accordance with the compared result; a common voltage generator to generate the common voltage having an application level instructed by the controller and to supply the common voltage to the liquid crystal display panel; a switching device for switching the common voltage having an application level instructed by the controller into the liquid crystal display panel; and a common voltage compensator for compensating the common voltage by means of the switching device on basis of a feedback common voltage from the liquid crystal display device, wherein the controller uses a predetermined look-up table to control the switching device to supply the common voltage level established in correspondence with the detected black and white brightness data levels to the liquid crystal display panel, wherein the common voltage generator includes first to nth common voltages level generators to generate a different level of first to nth common voltages (wherein n is an integer larger than 2), wherein the switching device includes first to nth switches connected in parallel between output terminals of the first to nth common voltages level generators and an input terminal of the common voltage compensator, wherein the first to nth switches are selectively switched by means of the controller, wherein if the controller switches the first switch to supply a level of first common voltage among first to nth common voltages, then the first switch directs the first common voltage to the liquid crystal display panel, wherein the first to nth common voltages are defined and the black brightness data levels and the white brightness data levels are established in correspondence with levels of the first to nth common voltages in the predetermined look-up table.