Investigate And Design Of A Multi-Line-Addressing Driver For STN-LCD Driver

Passive matrix supertwisted nematic (STN) LC displays are commonly used for medium information content displays such as in mobile phones because good image quality and low power consumption can be obtained with the low manufacturing costs inherent in passive matrix displays. Conventional line-by-line STN addressing causes reduced brightness and contrast ratio in STN panels fast enough for motion display.Active Addressing drive achieves this behavior by introducing multiple selection pulses that are distributed throughout the frame. With more selection pulses per frame, allowing it to properly react to the RMS voltage of the drive waveform for optimum brightness and contrast.Based on the research of LCD display system and analysis of function and architecture of LCD driver, this dissertation presents a shortcoming of traditional LCD Line-by-Line addressing method. Moreover, investigate special algorithm to implement Multiple Line Addressing scanning technology based on a Hadamard Matrix. In detail, we optimized design the Mtrix architecture, It will reduce the states of the algorithm FSM. By 4 line addressing method, the bias voltages of coloumn driver changed form 5 to 4,so that the power and area will be cut down as well.We have designing and verification a circuit with complexes function for scanning dot matrix STN LCD with TOP-Down design topology. We have optimized the access of embed SRAM, with the result of data transfer more efficeny. Implement the interface based of I2C bus.Furthermore this circuit were simulated with of CSMC 0.5u CMOS technology lib. The 4 line addressing method comsumed about 0.3% more power compared to the line-by-line addressing, but the waveform is better for dynamic display.