Study on the Embedded Gate Driver and Touch Circuit Based on Amorphous Silicon TFT Technology
|關鍵字:||液晶顯示器;閘極驅動電路;觸控面板;Thin film transistor liquid crystal display (TFT-LCD);Gate driver;Touch panel|
It is popular and inevitable for us to have many instruments with display screens in our life. The requirements of qualities whatever in image or appearance of apparatus have become more sophisticated. A revolutionary technology of TFT LCDs has been developed quickly which is system-on-panel (SOP) applications. However, SOP application has the potential to realize compact, highly reliable, and high resolution display by integrating functional circuits within a display. Besides, the cost of panel becomes lower, as well as the higher yield rate can be achieved. In this thesis, we proposed two main circuitries for TFT LCDs; the first one is a bi-directional gate driver. It has been designed and fabricated by amorphous silicon (a-Si) technology. With utilizing four clock signals in the design of gate driver on array (GOA), the pull-up transistor has ability for output charging and discharging. Moreover, lower duty cycle of clock signals can decrease static power loss to further reduce the overall power consumption and suppress the degradation of devices. The proposed gate driver has been successfully demonstrated in a 4.5-inch (1620xRGBx960) TFT-LCD panel and passed reliability tests of the cell phone standard. The second is an in-cell touch circuit which includes hybrid-type touch sensors and readout circuits. This hybrid-type touch sensor enables wide sensing range owing to integrated with liquid-crystal capacitive and optical sensors. Furthermore, an on-glass readout circuit for hybrid-type touch sensors is verified. The switched-capacitor (SC) technique is applied to eliminate the voltage variation from the operation time and manufacture process for analog-to-digital converter (ADC). The minimum detectable voltage difference of the ADC is 1V. By applying the analog-to-digital converter, the touched and untouched events can be converted to the digital output.
|Appears in Collections:||Thesis|