An embedded analog spatial filter design of the current-mode CMOS image sensor

This investigation presents an embedded analog spatial filter, EASF, in a current-mode CMOS image sensor. The EASF successfully identifies the output value of the pixel in B/W so as to benefit specific real world applications. Over the last few years, image quality has been improved by better progress in CMOS process technology, however, low cost issue regarding the integration of backend circuit still is an important competition point in imager design. Embedding an analog mask filter in a CMOS image sensor not only reduces cost, but also improves speed and simplicity of design integration with the backend image processing circuit. In this paper, a 66 × 66 embedded sensor array has been implemented in TSMC 0.35 μm CMOS process. Each pixel occupies a 13.8 μm × 9.8 μm area with a fill factor of 31.2%. The power consumption is 71.14m W when the sensor operates at 32 frames/sec.