1 Computer – Aided Design, Verification and Visualization of Digital Circuits Based on Current – Mode Gates

Abstract- The paper deals with the problem of designing digital circuits with the current-mode gates- novel digital gates operating with constant, continuous power supply current. The purpose is the provision of a high level of noise immunity of the chips, which compose both analog and digital circuits. The logical properties of the current-mode gates and logic (algebra) differ from classical voltage-mode gates and Boolean algebra respectively. Therefore, in this paper, the approaches to design of digital circuits based on current-mode gates are presented. Based on the first of these approaches, the computer-aided procedure, which allows to design, to verify and to visualize the current-mode digital circuits is proposed. This procedure is based on formulas for the conversion of logic expressions from Boolean algebra, VHDL descriptions of the current-mode circuits and the standard VHDL simulator (for example, Active-HDL), in which current-mode table of resolution and current-mode gate libraries should be included. The designed current-mode circuits are characterized by approximately equal hardware overheads in comparison with the similar circuits based on the classical voltage type of gates. Keywords-Current-Mode Gates, Analog-Digital Circuits. I