Desigh Of The Digital CMOS Image Sensor

With the development of computer technology and multimedia, we need a kind of image-capture-system which can input image data into private computer. Now CMOS technology has grown up ,so the combination of CMOS technology and the needs of market causes CMOS digital image sensor.We have studied many theories and projects, then we designed a new CMOS image sensor on the base. The following is main content of our thesis.The first, we analyze the system operation theory of CMOS image sensor with pixel level ADC(A/D Converter). It is made up of three sections: pixel array, clock signal generator and SAM(Sequential Access Memory). Every pixel generates a bit data after front half of the clock cycle, then the pixel array generate a bit plane which is stored in SAM. The data in SAM will be read out during the hind half of the clock cycle.The second, in order to improve the performance of the sensor, we have designed the pixel circuit which is very important. In this thesis, after studying some kinds of pixel circuits, we present a new pixel circuit which is based on improved flash A/D converter. We also have improved the pixel circuit according simulation results.The third, the whole circuit of digital CMOS image sensor is presented. The circuits of Pixel array, clock signal generator and SAM have been improved on the base of simulation.The last, we design the layout of pixel circuit with full-custom method And the layout of the pixel array is presented on the base of pixel circuit layout.