Low power current comparator cell for weak current operations
In this paper, we present a novel current comparator cell that converts a current signal to a two-level voltage through an adaptive thresholding. By applying a special compensation scheme, the non-uniformity of the threshold value in an array of such cells is lowered to less than 1%. The comparator cell can work at extremely low input currents, with the power dissipation in the range of nono-Watts or lower. The proposed circuit is simple and operates at high speed, since the operation of the cell is not dependent on a charge accumulation process. It can be fabricated in a single poly process, thus reducing the cost and also making it compatible with digital technology.