A Gray-coded digital-to-analog converter for a mixed-mode processor array

In this paper we propose a Gray-coded digital-to-analog converter (DAC) structure that has been validated with simulations. The DAC is designed for a cellular nonlinear network (CNN)-type mixed-mode array processor intended for real time image processing applications. With digital I/O operations, required bias values and also an input image can be loaded very quickly and easily stored into the array structure. However, the computing inside the cells is analog. Because of that, a DAC has to be included into every cell.