Binary Addressing Technique With Duty Cycle Control for LCDs

Abstract

Abstract-Introduction of duty cycle in the binary addressing technique is proposed to enable integration of liquid crystal display drivers with a digital system in a single chip. An analysis of this technique with duty-cycle control is presented. Effects of dutycycle control on brightness uniformity of pixels in the liquid crystal display are discussed. A system on chip implementation of the technique is also demonstrated.Index Terms-Displays, duty-cycle control, liquid crystal display ( LCD), matrix addressing and multiplexing.

Power Dissipation in Multi-Line Addressed Liquid-Crystal Displays

“…Hence, all the rows in the matrix display are selected with voltages corresponding to an -bit binary pattern. Column (data) voltage is obtained by comparing the select and data patterns such that the voltage is favorable to maximum number of pixels in the column as explained in [2] and [7]. The rows are selected with voltages corresponding to all the binary patterns (equivalent to a set of Rademacher functions) to complete a cycle.…”

“…Our objective is to analyze the power dissipation in the driver circuit of displays that are addressed with BAT, HAT,and IHAT. Brightness nonuniformity, due to distortions in the addressing waveforms, can be reduced by forcing the voltage across the pixels to zero for a short duration of time at the beginning or end of the select time [6], [7]. Therefore, we have also estimated the power dissipation of BAT, HAT, and IHAT when such duty cycle control is introduced in them.…”

Reducing power consumption in liquid-crystal displays

“…This technique will be referred to as line-by-line addressing with duty-cycle control. An introduction of a duty cycle has the advantage of good brightness uniformity of pixels [4]. Although the number of transitions is the same across all pixels, the power consumption depends on the number of pixels in the ON and OFF states because the capacitance of the pixel depends on its state.…”