INTRODUCTION TO CIRCUIT SIMULATION

EC302- COMPUTER AIDED DESIGN

What is CIRCUIT SIMULATION?

process of IMITATING the behaviour of electronic components in a circuit.

This is done using a specific electronic circuit simulation package.

Why?

TO DETECT the PROBLEM of the circuit before building them.

TO ENHANCES THE DESIGNS of the circuits.

Why?

TO VERIFY the OPERATION of the designed circuit.

Output can be in voltage distribution, current flow, waveforms, frequency response curve, switching speed in digital circuits.

TO REDUCES the COST and TIME spent in project design.

How? using any electronic circuit simulation

package or software such as;i. Pspiceii. Protel iii. Orcadiv. Cadancev. Mentor Graphics

DESIGN AND SIMULATION PROCESS

STEP-BY-STEP GUIDELINES

DESIGN & SIMULATION PROCESS Flowchart

TYPES OF SIMULATION CIRCUITS, METHODS &

ANALYSIS

Types Of Simulation Circuits There are FOUR

types of circuit:1. Analog Circuit

2. Digital Circuit

Circuit that consists of passive and/or active analog components.

Circuit that consists of digital components such as logic gates and digital devices.

Types Of Simulation Circuits3. Mixed-Signal

Circuit

4. Integrated Circuit

Circuit that combines analog and digital components.

The internal circuit of an IC, transistors and gets.

Simulation Methods

There are THREE methods of simulation:

1. Circuit Level An analog circuit is simulated and results i.e. voltage

drop, current flow, noise, impedance in the circuit are

obtained.

2. Logic LevelA digital circuit is simulated and the logic level of the inputs and outputs are obtained.

3. System Levelto determine the characteristics of a system such as the design of a telecommunication network, losses due to the cabling and the quality of transmitted and recepted signals between two distant locations.

Simulation Methods

3. System Levelto determine the characteristics of a system i.e. the design of a telecommunication network. Characteristics such as losses due to the cabling and the quality of transmitted and recepted signals between two distant locations can be determined.

Simulation Analysis There are FOUR types of analysis used in

simulation process.

1. DC Analysis -- Analysis circuit that use DC as source.

2. Transient Analysis -- Analysis how o/p varied with time.

Simulation Analysis

3. AC Analysis -- Analysis performance in small-signal AC source circuit.

4. Fourier Analysis -- Analysis frequency component

of any voltage or current.

CONCLUSION

Simulation helps us to test our circuits before building it.

However theory and calculations, will always guide us to predict the output of a circuits.