Electronic circuit design comprises the analysis and synthesis of electronic circuits.
Methods
To design any electrical circuit, either
analog
Analog or analogue may refer to:
Computing and electronics
* Analog signal, in which information is encoded in a continuous variable
** Analog device, an apparatus that operates on analog signals
*** Analog electronics, circuits which use analog ...
or
digital
Digital usually refers to something using discrete digits, often binary digits.
Businesses
*Digital bank, a form of financial institution
*Digital Equipment Corporation (DEC) or Digital, a computer company
*Digital Research (DR or DRI), a software ...
,
electrical engineers
Electrical engineering is an engineering discipline concerned with the study, design, and application of equipment, devices, and systems that use electricity, electronics, and electromagnetism. It emerged as an identifiable occupation in th ...
need to be able to predict the voltages and currents at all places within the circuit.
Linear circuit
A linear circuit is an electronic circuit which obeys the superposition principle. This means that the output of the circuit ''F(x)'' when a linear combination of signals ''ax1(t) + bx2(t)'' is applied to it is equal to the linear combination o ...
s, that is, circuits wherein the outputs are linearly dependent on the inputs, can be analyzed by hand using
complex analysis
Complex analysis, traditionally known as the theory of functions of a complex variable, is the branch of mathematical analysis that investigates functions of complex numbers. It is helpful in many branches of mathematics, including algebraic ...
. Simple nonlinear circuits can also be analyzed in this way. Specialized software has been created to analyze circuits that are either too complicated or too nonlinear to analyze by hand.
Circuit simulation software allows engineers to design circuits more efficiently, reducing the time cost and risk of error involved in building circuit prototypes. Some of these make use of hardware description languages such as
VHDL
VHDL (Very High Speed Integrated Circuit Program, VHSIC Hardware Description Language) is a hardware description language that can model the behavior and structure of Digital electronics, digital systems at multiple levels of abstraction, ran ...
or
Verilog
Verilog, standardized as IEEE 1364, is a hardware description language (HDL) used to model electronic systems. It is most commonly used in the design and verification of digital circuits, with the highest level of abstraction being at the re ...
.
Network simulation software
More complex circuits are analyzed with circuit simulation software such as
SPICE
In the culinary arts, a spice is any seed, fruit, root, Bark (botany), bark, or other plant substance in a form primarily used for flavoring or coloring food. Spices are distinguished from herbs, which are the leaves, flowers, or stems of pl ...
and
EMTP.
Linearization around operating point
When faced with a new circuit, the software first tries to find a
steady state solution wherein all the nodes conform to
Kirchhoff's Current Law
Kirchhoff's circuit laws are two Equality (mathematics), equalities that deal with the Electric current, current and potential difference (commonly known as voltage) in the lumped element model of electrical circuits. They were first described in ...
''and'' the voltages across and through each element of the circuit conform to the voltage/current equations governing that element.
Once the steady state solution is found, the software can analyze the response to perturbations using piecewise approximation, harmonic balance or other methods.
Piece-wise linear approximation
Software such as the
PLECS
PLECS ( Piecewise Linear Electrical Circuit Simulation) is a software tool for system-level simulations of electrical circuits developed by Plexim. It is especially designed for power electronics but can be used for any electrical network. PLEC ...
interface to
Simulink
Simulink is a MATLAB-based graphical programming environment for modeling, simulating and analyzing multidomain dynamical systems. Its primary interface is a graphical block diagramming tool and a customizable set of block libraries. It offe ...
uses
piecewise linear approximation of the equations governing the elements of a circuit. The circuit is treated as a completely linear network of
ideal diodes. Every time a diode switches from on to off or vice versa, the configuration of the linear network changes. Adding more detail to the approximation of equations increases the accuracy of the simulation, but also increases its running time.
Synthesis
Simple circuits may be designed by connecting a number of elements or functional blocks such as integrated circuits.
More complex digital circuits are typically designed with the aid of computer software. Logic circuits (and sometimes mixed mode circuits) are often described in such hardware description languages as
HDL,
VHDL
VHDL (Very High Speed Integrated Circuit Program, VHSIC Hardware Description Language) is a hardware description language that can model the behavior and structure of Digital electronics, digital systems at multiple levels of abstraction, ran ...
or
Verilog
Verilog, standardized as IEEE 1364, is a hardware description language (HDL) used to model electronic systems. It is most commonly used in the design and verification of digital circuits, with the highest level of abstraction being at the re ...
, then synthesized using a
logic synthesis
In computer engineering, logic synthesis is a process by which an abstract specification of desired circuit behavior, typically at register transfer level (RTL), is turned into a design implementation in terms of logic gates, typically by a co ...
engine.
See also
*
Circuit design
In electrical engineering, the process of circuit design can cover systems ranging from complex electronic systems down to the individual transistors within an integrated circuit. One person can often do the design process without needing a pl ...
*
Integrated circuit design
Integrated circuit design, semiconductor design, chip design or IC design, is a sub-field of electronics engineering, encompassing the particular Boolean logic, logic and circuit design techniques required to design integrated circuits (ICs). A ...
References
{{Design
Electronic design
Design
A design is the concept or proposal for an object, process, or system. The word ''design'' refers to something that is or has been intentionally created by a thinking agent, and is sometimes used to refer to the inherent nature of something ...