CircuitLogix
Encyclopedia
CircuitLogix is a software electronic circuit simulator
which uses PSpice
to simulate thousands of electronic devices, models, and circuits. A version of CircuitLogix with fewer models, simulation, and export features is available free of charge to students after registration
. CircuitLogix supports analog
, digital
, and mixed-signal circuits, and its SPICE
simulation gives accurate real-world results. The graphic user interface allows students to quickly and easily draw, modify and combine analog and digital circuit diagrams.
CircuitLogix was developed by Dr. Colin Simpson, an electronics professor at George Brown College
, in Toronto
, Canada
, and John (Bud) Skinner, a computer programmer. The electronics program has won awards including the Award of Excellence from the Association of Canadian Community Colleges
(ACCC). CircuitLogix is used exclusively as the electronic circuit simulation tool for the George Brown College Electronics Technician distance education program
, which is the largest Electronics technician
program in the world with over 4,000 students in 37 countries .
The professional version of CircuitLogix (CircuitLogix Pro) includes over 10,000 device models, as well as 8 virtual instruments. It also includes 3DLab, which is a software product that combines an interactive 3-dimensional learning environment and electronic devices and tools to enhance the user's comprehension of electronics. 3DLab virtual components include batteries
, switches, motors
, lamps, resistors, inductors, capacitors and instruments including oscilloscopes, Signal generator
s, and frequency counter
s.
Fast, accurate simulation of electronic circuits is essential because it provides the information needed to perform accurate analysis of circuit behavior. SPICE
simulators are used to verify that analog and mixed-signal circuits will yield the expected outputs. A schematic netlist file and circuit input values are fed to the SPICE software, which simulates the circuit's behavior for a specified length of time. CircuitLogix allows for the observation of voltage and current levels at any circuit node as they change with frequency and time. It allows for obtaining accurate results even when simulating complex circuits where hierarchical blocks are reused. The CircuitLogix simulation engine is based on Berkeley SPICE, and contains a GUI
to make circuit design easier and more efficient.
The CircuitLogix 32-bit SPICE engine is interactive, allowing, for example, the frequency
of sources to be changed, potentiometer
s adjusted, and switches thrown during simulation. The SPICE engine is fully integrated with the schematic capture and waveform
tools; CircuitLogix passes schematic edits to the simulator automatically while running. Components such as fuses, LED
s and controlled switches are automatically updated in the schematic as the simulation runs.
CircuitLogix simulates analog
, digital
, and mixed analog-digital circuits. The simulator first divides the circuit into analog and digital portions. The analog circuitry is simulated with the time-step driven SPICE engine, while the digital parts are simulated separately with an event-driven simulation engine. The CircuitLogix digital engine was developed directly in .NET
, faster than SPICE macros. Because the simulator automatically performs signal conversion, it is possible to connect any analog or digital part to any other. The system’s model library contains hybrid parts for analog-to-digital and digital-to-analog conversion.
CircuitLogix is a mixed-mode schematic editor
, and includes both analog and event-driven simulation capabilities: any simulation may contain components that are analog, event driven (digital or sampled-data), or a combination of both. An entire mixed signal analysis can be driven from one integrated schematic. All the digital models in CircuitLogix provide accurate specification of propagation time and rise/fall time delays.
The event-driven algorithm
used by CircuitLogix is general-purpose and supports non-digital types of data. For example, elements can use real or integer
values to simulate DSP functions or sampled data filters. Because the event-driven algorithm is faster than the standard SPICE matrix, simulation time is greatly reduced for circuits that use event-driven models in place of analog models.
Mixed-mode simulation is handled on three levels by CircuitLogix: (a) with primitive digital elements that use timing models and a built-in 12-state digital logic simulator, (b) with subcircuit models that use the actual transistor topology
of the integrated circuit
, and finally, (c) with In-line Boolean logic
expressions. These two modeling techniques use SPICE to solve a problem while the third method, digital primitives, uses mixed-mode capability.
Semiconductors: Semiconductor Resistors & Capacitors, Diodes, Schottky & Zener Diode
s, Bridge rectifiers, Varactor
Displays, indicators, switches: LEDs
, 7-Segment LEDs, Hex display, Hex key, Logic display, NC push-button, NO push button, SPDT PB, Piezo buzzer, Pulser, Latch coil, Polar latch, Rocket, SCOPE, Stepper, Stoplight, Window
Digital primitives: Gates, DeMorgan symboled gates, buffers, inverters, flip-flops
Digital ICs: 1K RAM, 32x8 PROM, complete selection of 40xx, 41xx, 45xx, 47xx, 74xxx IC's
Linear ICs: Op Amps, Comparator
s, Timers, Buffers, CDAs, Modulators, A/D converter
s & D/A converter
s, PLL, VCO
Transistors, FET
: BJT, IGBT, UJT, PUT, MESFET
, MOSFET
, Darlington transistor
Relays: Control relay, SPST, DPDT, Individual contacts and coils (enable creation of any relay)
Supplies, Sources: Battery
, Voltage Terminal, Signal generator
, I Source, V Source, I->I Source, V->I Source, I->Switch,V->Switch, I->V Source, V->V Source
Math devices: A wide variety of devices for manipulating quantities
Miscellaneous Devices: Crystals, Fuses
, Transformer
s, DC Motor
, F-V & V-F converters
Transmission lines: Lossless, Lossy, and Uniform Distributed RC
Vacuum Tubes: 12AU7, 12AX7, 5879, 6L6GC, 6SN7, 7199P, 7199T
Instruments: Oscilloscope
, Digital Multimeter
, Bode plotter, Curve tracer, Data Sequencer, Signal generator, Logic analyzer
, Logic probe
, Logic Pulser
Simulation Controls: Initial Condition and Nodeset devices
Miscellaneous: Optoisolators, Photodiodes, Voltage regulator
s, References, SCRs, Triacs
Electronic circuit simulation
Electronic circuit simulation uses mathematical models to replicate the behavior of an actual electronic device or circuit.Simulation software allows for modeling of circuit operation and is an invaluable analysis tool...
which uses PSpice
PSPICE
PSpice is a SPICE analog circuit and digital logic simulation program for Microsoft Windows. The name is an acronym for Personal Simulation Program with Integrated Circuit Emphasis.- History :...
to simulate thousands of electronic devices, models, and circuits. A version of CircuitLogix with fewer models, simulation, and export features is available free of charge to students after registration
Registered user
A registered user is one who uses a program or a website and provides his/her credentials, effectively proving his/her identity.-Technical differences:...
. CircuitLogix supports analog
Analog signal
An analog or analogue signal is any continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal. It differs from a digital signal in terms of small fluctuations in the signal which are...
, digital
Digital
A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...
, and mixed-signal circuits, and its SPICE
SPICE
SPICE is a general-purpose, open source analog electronic circuit simulator.It is a powerful program that is used in integrated circuit and board-level design to check the integrity of circuit designs and to predict circuit behavior.- Introduction :Unlike board-level designs composed of discrete...
simulation gives accurate real-world results. The graphic user interface allows students to quickly and easily draw, modify and combine analog and digital circuit diagrams.
CircuitLogix was developed by Dr. Colin Simpson, an electronics professor at George Brown College
George Brown College
George Brown College is a public, fully accredited college of applied arts and technology with three full campuses in downtown Toronto, Ontario...
, in Toronto
Toronto
Toronto is the provincial capital of Ontario and the largest city in Canada. It is located in Southern Ontario on the northwestern shore of Lake Ontario. A relatively modern city, Toronto's history dates back to the late-18th century, when its land was first purchased by the British monarchy from...
, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...
, and John (Bud) Skinner, a computer programmer. The electronics program has won awards including the Award of Excellence from the Association of Canadian Community Colleges
Association of Canadian Community Colleges
The Association of Canadian Community Colleges is a national association formed in 1972 to represent the interests of its member institutions to government and industry. Membership is voluntary and open to publicly-funded community colleges in Canada or institutions that may also be referred to as...
(ACCC). CircuitLogix is used exclusively as the electronic circuit simulation tool for the George Brown College Electronics Technician distance education program
Electronics Technician distance education program
The Electronics Technician Distance Education program provides flexible, skills-based training in electronics. It has been developed for adult learners pursuing electronics technician-level training through independent study, specifically students who cannot attend college full-time because of...
, which is the largest Electronics technician
Electronics technician
Electronics Technicians help design, develop, test, manufacture, and install electrical and electronic equipment such as communication equipment, medical monitoring devices, navigational equipment, and computers. They may be employed in product evaluation and testing, using measuring and...
program in the world with over 4,000 students in 37 countries .
The professional version of CircuitLogix (CircuitLogix Pro) includes over 10,000 device models, as well as 8 virtual instruments. It also includes 3DLab, which is a software product that combines an interactive 3-dimensional learning environment and electronic devices and tools to enhance the user's comprehension of electronics. 3DLab virtual components include batteries
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
, switches, motors
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...
, lamps, resistors, inductors, capacitors and instruments including oscilloscopes, Signal generator
Signal generator
Signal generators, also known variously as function generators, RF and microwave signal generators, pitch generators, arbitrary waveform generators, digital pattern generators or frequency generators are electronic devices that generate repeating or non-repeating electronic signals...
s, and frequency counter
Frequency counter
A frequency counter is an electronic instrument, or component of one, that is used for measuring frequency. Frequency is defined as the number of events of a particular sort occurring in a set period of time. Frequency counters usually measure the number of oscillations or pulses per second in a...
s.
Overview
SPICE
SPICE is a general-purpose, open source analog electronic circuit simulator.It is a powerful program that is used in integrated circuit and board-level design to check the integrity of circuit designs and to predict circuit behavior.- Introduction :Unlike board-level designs composed of discrete...
simulators are used to verify that analog and mixed-signal circuits will yield the expected outputs. A schematic netlist file and circuit input values are fed to the SPICE software, which simulates the circuit's behavior for a specified length of time. CircuitLogix allows for the observation of voltage and current levels at any circuit node as they change with frequency and time. It allows for obtaining accurate results even when simulating complex circuits where hierarchical blocks are reused. The CircuitLogix simulation engine is based on Berkeley SPICE, and contains a GUI
Gui
Gui or guee is a generic term to refer to grilled dishes in Korean cuisine. These most commonly have meat or fish as their primary ingredient, but may in some cases also comprise grilled vegetables or other vegetarian ingredients. The term derives from the verb, "gupda" in Korean, which literally...
to make circuit design easier and more efficient.
The CircuitLogix 32-bit SPICE engine is interactive, allowing, for example, the frequency
Frequency
Frequency is the number of occurrences of a repeating event per unit time. It is also referred to as temporal frequency.The period is the duration of one cycle in a repeating event, so the period is the reciprocal of the frequency...
of sources to be changed, potentiometer
Potentiometer
A potentiometer , informally, a pot, is a three-terminal resistor with a sliding contact that forms an adjustable voltage divider. If only two terminals are used , it acts as a variable resistor or rheostat. Potentiometers are commonly used to control electrical devices such as volume controls on...
s adjusted, and switches thrown during simulation. The SPICE engine is fully integrated with the schematic capture and waveform
Waveform
Waveform means the shape and form of a signal such as a wave moving in a physical medium or an abstract representation.In many cases the medium in which the wave is being propagated does not permit a direct visual image of the form. In these cases, the term 'waveform' refers to the shape of a graph...
tools; CircuitLogix passes schematic edits to the simulator automatically while running. Components such as fuses, LED
LEd
LEd is a TeX/LaTeX editing software working under Microsoft Windows. It is a freeware product....
s and controlled switches are automatically updated in the schematic as the simulation runs.
CircuitLogix simulates analog
Analog signal
An analog or analogue signal is any continuous signal for which the time varying feature of the signal is a representation of some other time varying quantity, i.e., analogous to another time varying signal. It differs from a digital signal in terms of small fluctuations in the signal which are...
, digital
Digital
A digital system is a data technology that uses discrete values. By contrast, non-digital systems use a continuous range of values to represent information...
, and mixed analog-digital circuits. The simulator first divides the circuit into analog and digital portions. The analog circuitry is simulated with the time-step driven SPICE engine, while the digital parts are simulated separately with an event-driven simulation engine. The CircuitLogix digital engine was developed directly in .NET
.NET Framework
The .NET Framework is a software framework that runs primarily on Microsoft Windows. It includes a large library and supports several programming languages which allows language interoperability...
, faster than SPICE macros. Because the simulator automatically performs signal conversion, it is possible to connect any analog or digital part to any other. The system’s model library contains hybrid parts for analog-to-digital and digital-to-analog conversion.
Mixed-mode simulation
Schematic editor
A Schematic editor is a tool for schematic capture of electrical circuits or electronic circuits.Schematic editors replaced manual drawing of schematic diagrams, but they still retain the capability of outputting schematics on specially formatted sheets...
, and includes both analog and event-driven simulation capabilities: any simulation may contain components that are analog, event driven (digital or sampled-data), or a combination of both. An entire mixed signal analysis can be driven from one integrated schematic. All the digital models in CircuitLogix provide accurate specification of propagation time and rise/fall time delays.
The event-driven algorithm
Algorithm
In mathematics and computer science, an algorithm is an effective method expressed as a finite list of well-defined instructions for calculating a function. Algorithms are used for calculation, data processing, and automated reasoning...
used by CircuitLogix is general-purpose and supports non-digital types of data. For example, elements can use real or integer
Integer
The integers are formed by the natural numbers together with the negatives of the non-zero natural numbers .They are known as Positive and Negative Integers respectively...
values to simulate DSP functions or sampled data filters. Because the event-driven algorithm is faster than the standard SPICE matrix, simulation time is greatly reduced for circuits that use event-driven models in place of analog models.
Mixed-mode simulation is handled on three levels by CircuitLogix: (a) with primitive digital elements that use timing models and a built-in 12-state digital logic simulator, (b) with subcircuit models that use the actual transistor topology
Topology
Topology is a major area of mathematics concerned with properties that are preserved under continuous deformations of objects, such as deformations that involve stretching, but no tearing or gluing...
of the integrated circuit
Integrated circuit
An integrated circuit or monolithic integrated circuit is an electronic circuit manufactured by the patterned diffusion of trace elements into the surface of a thin substrate of semiconductor material...
, and finally, (c) with In-line Boolean logic
Boolean logic
Boolean algebra is a logical calculus of truth values, developed by George Boole in the 1840s. It resembles the algebra of real numbers, but with the numeric operations of multiplication xy, addition x + y, and negation −x replaced by the respective logical operations of...
expressions. These two modeling techniques use SPICE to solve a problem while the third method, digital primitives, uses mixed-mode capability.
Component library
The component library includes:Semiconductors: Semiconductor Resistors & Capacitors, Diodes, Schottky & Zener Diode
Zener diode
A Zener diode is a special kind of diode which allows current to flow in the forward direction in the same manner as an ideal diode, but will also permit it to flow in the reverse direction when the voltage is above a certain value known as the breakdown voltage, "Zener knee voltage" or "Zener...
s, Bridge rectifiers, Varactor
Displays, indicators, switches: LEDs
LEDS
LEDS can be initials for:* Law Enforcement Data System* Link Eleven Display System* Low Energy Dislocation Structure* Land Electronic Defence System * LEDs * Life-Events and Difficulties Schedule...
, 7-Segment LEDs, Hex display, Hex key, Logic display, NC push-button, NO push button, SPDT PB, Piezo buzzer, Pulser, Latch coil, Polar latch, Rocket, SCOPE, Stepper, Stoplight, Window
Digital primitives: Gates, DeMorgan symboled gates, buffers, inverters, flip-flops
Digital ICs: 1K RAM, 32x8 PROM, complete selection of 40xx, 41xx, 45xx, 47xx, 74xxx IC's
Linear ICs: Op Amps, Comparator
Comparator
In electronics, a comparator is a device that compares two voltages or currents and switches its output to indicate which is larger. They are commonly used in devices such as Analog-to-digital converters .- Input voltage range :...
s, Timers, Buffers, CDAs, Modulators, A/D converter
Analog-to-digital converter
An analog-to-digital converter is a device that converts a continuous quantity to a discrete time digital representation. An ADC may also provide an isolated measurement...
s & D/A converter
Digital-to-analog converter
In electronics, a digital-to-analog converter is a device that converts a digital code to an analog signal . An analog-to-digital converter performs the reverse operation...
s, PLL, VCO
Voltage-controlled oscillator
A voltage-controlled oscillator or VCO is an electronic oscillator designed to be controlled in oscillation frequency by a voltage input. The frequency of oscillation is varied by the applied DC voltage, while modulating signals may also be fed into the VCO to cause frequency modulation or phase...
Transistors, FET
Fet
Fet is a municipality in Akershus county, Norway. It is part of the Romerike traditional region. The administrative centre of the municipality is the village of Fetsund.Fet was established as a municipality on 1 January 1838...
: BJT, IGBT, UJT, PUT, MESFET
MESFET
MESFET stands for metal semiconductor field effect transistor. It is quite similar to a JFET in construction and terminology. The difference is that instead of using a p-n junction for a gate, a Schottky junction is used...
, MOSFET
MOSFET
The metal–oxide–semiconductor field-effect transistor is a transistor used for amplifying or switching electronic signals. The basic principle of this kind of transistor was first patented by Julius Edgar Lilienfeld in 1925...
, Darlington transistor
Darlington transistor
In electronics, the Darlington transistor is a compound structure consisting of two bipolar transistors connected in such a way that the current amplified by the first transistor is amplified further by the second one...
Relays: Control relay, SPST, DPDT, Individual contacts and coils (enable creation of any relay)
Supplies, Sources: Battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...
, Voltage Terminal, Signal generator
Signal generator
Signal generators, also known variously as function generators, RF and microwave signal generators, pitch generators, arbitrary waveform generators, digital pattern generators or frequency generators are electronic devices that generate repeating or non-repeating electronic signals...
, I Source, V Source, I->I Source, V->I Source, I->Switch,V->Switch, I->V Source, V->V Source
Math devices: A wide variety of devices for manipulating quantities
Miscellaneous Devices: Crystals, Fuses
Fuse (electrical)
In electronics and electrical engineering, a fuse is a type of low resistance resistor that acts as a sacrificial device to provide overcurrent protection, of either the load or source circuit...
, Transformer
Transformer
A transformer is a device that transfers electrical energy from one circuit to another through inductively coupled conductors—the transformer's coils. A varying current in the first or primary winding creates a varying magnetic flux in the transformer's core and thus a varying magnetic field...
s, DC Motor
DC motor
A DC motor is an electric motor that runs on direct current electricity.-Brush:The brushed DC electric motor generates torque directly from DC power supplied to the motor by using internal commutation, stationary magnets , and rotating electrical magnets.Like all electric motors or generators,...
, F-V & V-F converters
Transmission lines: Lossless, Lossy, and Uniform Distributed RC
Vacuum Tubes: 12AU7, 12AX7, 5879, 6L6GC, 6SN7, 7199P, 7199T
Instruments: Oscilloscope
Oscilloscope
An oscilloscope is a type of electronic test instrument that allows observation of constantly varying signal voltages, usually as a two-dimensional graph of one or more electrical potential differences using the vertical or 'Y' axis, plotted as a function of time,...
, Digital Multimeter
Multimeter
A multimeter or a multitester, also known as a VOM , is an electronic measuring instrument that combines several measurement functions in one unit. A typical multimeter may include features such as the ability to measure voltage, current and resistance...
, Bode plotter, Curve tracer, Data Sequencer, Signal generator, Logic analyzer
Logic analyzer
A logic analyzer is an electronic instrument which displays signals in a digital circuit. A logic analyzer may convert the captured data into timing diagrams, protocol decodes, state machine traces, assembly language, or correlate assembly with source-level software.Presently, there are three...
, Logic probe
Logic probe
A logic probe is a hand-held pen-like test probe used for analyzing and troubleshooting the logical states of a digital circuit. While most are powered by the circuit under test, some devices use batteries...
, Logic Pulser
Simulation Controls: Initial Condition and Nodeset devices
Miscellaneous: Optoisolators, Photodiodes, Voltage regulator
Voltage regulator
A voltage regulator is an electrical regulator designed to automatically maintain a constant voltage level. A voltage regulator may be a simple "feed-forward" design or may include negative feedback control loops. It may use an electromechanical mechanism, or electronic components...
s, References, SCRs, Triacs