Low Power Techniques for Gray Shades in Liquid Crystal Displays

Abstract

Abstract-The largest transition in the select waveform of successive approximation technique is eliminated to reduce power dissipation in liquid crystal displays. Power dissipation in the driver circuit is analyzed for gray scale images by considering three select sequences. They are compared and a new select sequence is proposed to achieve low power dissipation. An additional pulse is introduced in the select waveform to reduce peak amplitude of select and data waveforms to achieve a low supply voltage for the driver circuit.

Methods to reduce power dissipation and supply voltage of LCD drivers

“…The waveform across the pixel when it is not selected (W non-sel ) is obtained by substituting V r = 0 in the above equation because the non-select voltage is zero. Thus, the rms voltage across a pixel is (5) Orthogonal functions are also represented in a matrix of the form O r×l . For displaying 'g' gray shades, 'g' orthogo-…”

“…2 Further, we have compared wavelet addressing 3 and two new techniques with the Successive Approximation Technique. 4 Power dissipation of the Successive Approximation Technique has been analyzed elsewhere 5 ; however, it is included here as a reference to evaluate the relative performance of the other line-by-line addressing techniques. A general description of the energymultiplexing technique is presented in the following section.…”

A unified parameterization technique for TFT-LCD panel design optimization

“…Additionally, to meet specified display performances of product, the designer has to tune the design parameters of the TFT-LCD pixel and circuit, which make the design of TFT-LCD panel complicated and timeconsuming. Investigative efforts up to now have intensively focused on design of panel circuits and systems [4][5][6], to the best of our knowledge; an efficient and multi-objective optimization platform for TFT-LCD panel design automation is still lack. Design using various CAD tools manually and repeatedly may increase the product manufacturing cost, prolong the product time to market, complicate the design procedures, and reduce the functional accuracy and device reliability.…”