Synthetic neural systems using current-mode circuits

An approach to the engineering of VLSI analog computing systems is presented. The approach emphasizes the role of currents as an appropriate signal representation, the need for low power dissipation, and the need for simplicity in the basic functional circuits. The design methodology is based on current-mode (CM) MOS circuits, and is inspired by the functional and organizational principles of biological neural circuits. The basic circuit blocks exploit the translinear properties of the MOS transistor in the subthreshold and use unidirectional current signals. Circuits for associative memories and silicon retinas are described