Electronic Circuit Simulation Research Articles

A three‐terminal piecewise‐linear modelling approach to dc analysis of transistor circuits

AbstractThe simulation of electronic circuits by computer has become an important part of present‐day circuit analysis and design, especially in the area of integrated circuit design. One of the goals in computer simulation of integrated circuits is to have a program ‘package’ for which the input consists of chip fabrication data (mask dimensions, impurity profiles, material data such as carrier lifetimes) and the output displays the complete circuit response. This requires both an efficient modelling approach and a fast circuit analysis method.In this paper a simulation method is described which generates dc responses (in the form of operating points or transfer characteristics) of transistor circuits directly from physical parameter data. The basis of the method is a two‐dimensional piecewise‐linear approach to the dc modelling of bipolar transistors. The model is directly used in a piecewise‐linear circuit analysis program to simulate the dc response of a given circuit.

Efficient computer simulation of distortion in electronic circuits

A general-purpose electronic-circuit simulation program is employed to efficiently compute second- and third-order distortion due to weak nonlinearities in bipolar junction transistor (BJT) circuits of arbitrary complexity. The method is based on the Volterra-series representation of the electronic circuit and is valid at all frequencies. The transistors are represented by a simple modified Ebers-Moll model, and the adjoint-network concept is employed to efficiently compute the contribution of each nonlinearity in the circuit to the distortion at the output. The method is illustrated with a practical electronic-circuit example.

An Application of the Analog Computer to Electronic Circuit Simulation

An Application of the Analog Computer to Electronic Circuit Simulation

AEDNET: A simulator for nonlinear networks

AEDNET is a system of digital computer programs for simulation of both linear and nonlinear electronic circuits. The system has two main features: 1) the ability to simulate the behavior of a wide class of nonlinear networks, and 2) the on-line use of a digital computer and its oscilloscope display unit for on-line interaction. AEDNET is written in the AED-0 language and it operates on the Project MAC time-sharing computer and the Electronic Systems Laboratory display unit. AEDNET simulates networks whose elements are nonlinear time-varying capacitors, resistors, inductors, and dependent and independent sources. The network is required to satisfy certain topological conditions, and the elements' characteristics are required to satisfy suitable Lipschitz conditions. Non-linear characteristics are represented in the computer either by a table or a subroutine. Elements with nonmonotonic characteristics are allowed, and the elements' characteristics are required to be continuous but not differentiable. Input to the program is given mainly by drawing the network diagram on the face of the oscilloscope, and assigning values to the network elements by typing on the console's teletype or by drawing the elements' characteristics. The output of the program gives the waveforms of the various network variables. Each variable can be displayed on the oscilloscope as a function of time or as a function of another network variable. After a network has been specified and the response calculated and displayed, the user can modify the network by changing both elements and topology, and then ask for a recalculation and redisplay. The object of this paper is to give a general description of AEDNET and a detailed consideration of the part of the system which sets the network equations and calculates the network response.