MULTISIM tutorialMULTISIM tutorial

Introduction to MultiSimIntroduction to MultiSim

Need For SimulationNeed For Simulation

For determination of parameters for For determination of parameters for complex circuits.complex circuits.

To test validity of the circuit.To test validity of the circuit. Generate mathematical models of Generate mathematical models of

electronic components.electronic components. Test performance without actually Test performance without actually

building the circuit .building the circuit . Calculating parameters of non-linear Calculating parameters of non-linear

devicesdevices

Simulation Basics (Analog Simulation Basics (Analog ckt)ckt)

G1 * e1 + (– k – G1)*e2 + k*e3 = I0 ……….(1)

-G1*e1 + (G1 + G2 + G3)*e2 – G3*e3 = 0….(2)

(-G3 + k)*e2 + (G4 + G3 – k)*e3 = 0………..(3)

Simulation BasicsSimulation Basics

SPICE input file: example(Simulation Program with Integrated Circuit Emphasis)

V1 1 0 10R1 1 2 1.5kR2 2 0 1k

How many nodes?

Do we need extra variables (e.g., voltage sources)?

Assemble the system matrix.

Solve.

Simulation Basics (Digital Simulation Basics (Digital ckt)ckt)

Digital Circuits: event-driven simulation Instead of ckt description its behaviour Instead of ckt description its behaviour

is defined.is defined. Only discrete levels of voltage.Only discrete levels of voltage.

Components AvailableComponents Available

Basic : resistors , capacitor , Basic : resistors , capacitor , inductor , potentiometer , inductor , potentiometer , transformer .transformer .

Switches : SPST , SPDT , DPDT.Switches : SPST , SPDT , DPDT. Sources : DC power , AC power , Sources : DC power , AC power ,

Ground , Vcc , Vdd. Ground , Vcc , Vdd.

…….Components.Components

Diodes : Si / Ge diodes , Zener Diodes : Si / Ge diodes , Zener diodes , LED .diodes , LED .

Transistors : BJT ( npn and pnp)Transistors : BJT ( npn and pnp)

FET ( MOSFET & JFET )FET ( MOSFET & JFET ) Analog IC : operational amp (eg. IC Analog IC : operational amp (eg. IC

741) ,741) ,

Timer IC 555. Timer IC 555.

And many moreAnd many more

Digital ComponentsDigital Components

Digital IC : available in TTL and CMOS Digital IC : available in TTL and CMOS families.families.

Basic gates : 7408 (AND) , 7404 (NOT) , Basic gates : 7408 (AND) , 7404 (NOT) , etc.etc.

MSI chips : 74151 (MUX) , 74138 MSI chips : 74151 (MUX) , 74138 (DEMUX) , 7483 (4 bit adder) , 7490 (DEMUX) , 7483 (4 bit adder) , 7490 (dec counter) , etc.(dec counter) , etc.

Indicators : HEX display , digital probe.Indicators : HEX display , digital probe.

Miscellaneous Miscellaneous ComponentsComponents

Crystals .Crystals . Voltage regulators (eg. LM317 , Voltage regulators (eg. LM317 ,

7805 , 7905).7805 , 7905). Fuse.Fuse. RF Components.RF Components. Transmission lines .Transmission lines .

InstrumentsInstruments

Multimeter : for current , voltage Multimeter : for current , voltage and resistance measurements in and resistance measurements in ac and dc modes.ac and dc modes.

Wattmeter : for power and power Wattmeter : for power and power factor measurement.factor measurement.

……InstrumentsInstruments

Function Generator : for generation Function Generator : for generation of waveforms such as sinusoidal , of waveforms such as sinusoidal , square , triangular , with controls for square , triangular , with controls for frequency , duty cycle, amplitude frequency , duty cycle, amplitude

Oscilloscope : to view output Oscilloscope : to view output waveforms with controls for time waveforms with controls for time base , Volt/div , trigger , X-Y mode base , Volt/div , trigger , X-Y mode and cursors 1 & 2 .and cursors 1 & 2 .

Analysis of CircuitsAnalysis of Circuits

It is carried out to test the It is carried out to test the behaviour of the circuit for various behaviour of the circuit for various inputs and/or varying conditions.inputs and/or varying conditions.

Setting up of the output variables :Setting up of the output variables :

Variables are nothing but nodes Variables are nothing but nodes whose behavior is to be monitored .whose behavior is to be monitored .

Setting of parameters to be varied.Setting of parameters to be varied.

Types of AnalysisTypes of Analysis

DC Operating Point Analysis AC Analysis Transient Analysis Fourier Analysis Noise Analysis Distortion Analysis DC Sweep Analysis

……Types of AnalysisTypes of Analysis

DC and AC Sensitivity Analyses Parameter Sweep Analysis Temperature Sweep Analysis Transfer Function Analysis Pole Zero Analysis RF Analyses (and more)(and more)

DC operating point DC operating point analysisanalysis

In this analysis all the ac sources In this analysis all the ac sources are zeroed out.are zeroed out.

Capacitors are assumed to be Capacitors are assumed to be open, inductors short circuited.open, inductors short circuited.

Used for Q point determination of Used for Q point determination of amplifier stage.amplifier stage.

AC AnalysisAC Analysis

All input sources are automatically switched internally to a sinusoidal waveform for analysis. AC analysis then calculates the AC circuit response as a function of frequency.

Used to calculate the Band width and/or Critical freq.

Transient AnalysisTransient Analysis

The circuit response is calculated The circuit response is calculated as a function of time.as a function of time.

Can be used to see the system Can be used to see the system response for a short duration of response for a short duration of time [ eg. Time = 0 to 0.0001 time [ eg. Time = 0 to 0.0001 seconds].seconds].

Used for observing step response Used for observing step response of the system.of the system.

Other Analyses...Other Analyses...

Parameter sweep : Specified Parameter sweep : Specified parameter of the active device is parameter of the active device is varied.varied.

Temperature sweep : Operating Temperature sweep : Operating temperature is varied.temperature is varied.

DC sweep analysis : The value from DC sweep analysis : The value from the source is incremented and another the source is incremented and another DC Operating Point is calculated.DC Operating Point is calculated.

General steps for General steps for simulationsimulation

Place components on the Place components on the workspace .workspace .

Connect components according to Connect components according to circuit diagram .circuit diagram .

Connect power supply and ground .Connect power supply and ground . Press the ‘ Simulation switch ’Press the ‘ Simulation switch ’ Observe the results and carry out Observe the results and carry out

the required analyses.the required analyses.

Some Special FeaturesSome Special Features

IC 555 Timer Wizard .IC 555 Timer Wizard . Filter wizard.Filter wizard. Dynamic measurement probe.Dynamic measurement probe. Virtual Lab instruments and Virtual Lab instruments and

components .components . Dependant sources.Dependant sources. Bill of materials.Bill of materials.

PrecautionsPrecautions

Each simulation must have a Each simulation must have a ground .ground .

Make sure all components are Make sure all components are connected properly.connected properly.

Check all component values.Check all component values. Place HB/SB connector to labeling Place HB/SB connector to labeling

a node.a node.