CMOS image sensor with mixed-signal processor array

We present a single-chip integration of a CMOS image sensor with an embedded flexible processing array and dedicated analog-to-digital converter. The processor array is designed to perform convolution and transformation algorithms with arbitrary kernels. It has been designed to carry out the multiplication of analog image data with given digital kernel coefficients and to add up the results. The processor array is an analog implementation of a highly parallel architecture which is scalable to any desired sensor resolution while preserving video-rate operation. A prototype implementation has been realized in a 0.6-mum CMOS technology. Switched current technique has been applied to obtain compact and robust circuits. The prototype's sensor resolution is 64 x 128 pixels. The processor array occupies a small chip area and consumes only a small percentage of the power (250 muW) of the whole image sensor.