Computer-Aided Circuit Design by Singular Imbedding

We give a new and powerful method for the direct solution of circuit design problems. The method begins with a prespecified topology and some or all elements undetermined in value. The designer imposes on the circuit any desired set of node-pair voltages, branch currents, or driving point and transfer immittances. Values of circuit elements that satisfy the constraints are directly calculated. This direct method of solution avoids the usual iterative analysis-optimization schemes, reducing computer times by up to three orders of magnitude. A linear set of design equations is formulated by choosing undetermined element currents and node voltages as the variables. Singular elements are introduced to impose the desired constraints. Inequality as well as equality constraints are permitted. Element values are determined from the solution of these equations. In this paper we emphasize our method of solution in relation to dc networks.