EC302 – Electronic Computer Aided DesignMOHD AT-TARMIZI BIN ABU HASSAN 013-3507201
FIRST WARNING !!!• NO excuse for who come late to my class• NO reconsider for any marks given• NO empty-talk in my class• NO delay assignments submitting• NO inappropriate wear• NO hang around in my class• NO stupid talk
CAD = Computer Aided Design• modeling of physical systems on computers• allowing both interactive and automatic analysis of design variants• expression of designs in a form suitable for manufacturing* Also known as CADD (Computer Aided Design & Drafting)
Type of Simulation Circuit• Analog• Digital• Mixed-signal
Type of Simulation• DC Analysis• DC Sweep Analysis• AC Analysis• Transfer Function Analysis• Transient Analysis
DC Analysis• Determination of steady-state response of the circuit when time-invariant DC sources are applied.
DC Sweep Analysis• Determination of response of the circuit when excitation, or any other component is varied over a range.
AC Analysis• a.k.a Frequency Domain Analysis• Determination of steady-state response of the circuit when sinusoidal excitation is applied mine the frequency response of the circuit.• The frequency of excitation can be varied to determine the frequency response of the circuit.
Transfer Function Analysis• Determination of small-signal transfer function with small-signal gain, input impedance, output impedance.
Transient Analysis• a.k.a Time Domain Analysis• Determination of variation of response of the circuit with respect to time.
Advantages of Simulation• able to provide users with practical feedback when designing real world systems• study a problem at several different levels of abstraction• can be used as an effective means for teaching or demonstrating concepts to students
Disadvantages of Simulation• computationally intensive processing required by some simulators• restricted by limited hardware platforms which cannot meet the computational demands of the simulator• introduce simplifying assumptions or heuristics into the simulator engine• computational complexity is to employ the hierarchical approach to design and simulation
Simulation Method• Circuit level• Logic level• System level
Design and Simulation Process Identify Project - A project or circuit to be designed is identified Design / Redesign Project - The project/circuit is designed based on theoryFail - The project designed is simulated using software Simulation package to produce results/outputs of the project operation - See whether the project actually works as in Testing simulation - The printed project/circuit board layout is PCB Design Layout designed and produced - An actual working model of the project is Prototype constructed
Netlist• Source Element• Passive Device Element• Active Device Element
Source element• The sources functions to supply the circuit with power supply or input waveforms. There are THREE (3) different types of sources used in simulation - DC Source - AC Source - Transient Source
DC Source• A source that generates dc voltage and dc current• There are two types of dc sources: – dependent source – independent source
AC Source• A source that generates sinusoidal waveforms at different frequencies with the same magnitude
Transient Source• A source that generates waveform whose amplitude changes with time• Examples of transient sources are: - Sine Waveform - Pulse Waveform - Polynomial Waveform - Exponential Waveform
Passive Device Element• Passive elements are electronic passive components• Example: - Resistor - Capacitor - Inductor - Transformer
Active Device Element• Active device elements are electronic components made of semiconductor material• Examples : - Diode - Bipolar Transistor (BJT) - Field-Effect Transistor (FET) - Integrated Circuit (IC)
Why do we need to simulate• A simulation is not used to figure out how a circuit works• It is important to know the theory of your design before you simulate
Why do we need to simulate• In the verification process, results generated by the simulation package will give information about the designed circuit
Output in verification process• Circuit Output - voltage distribution, current flow, waveforms, frequency response curve, switching speed in digital circuits• circuit operation sensitivity towards change in other component values• change in circuit characteristics due to temperature change• circuit elements parameters could be modify for optimum operation
QUIZ 1• Give at least FOUR (4) types of simulation.• Draw the flow chart for simulation process. P/S : Don’t forget to write down your name, reg. no, i/c no, class, and assessment no.
LAST WARNING !!!• NO excuse for who come late to my class• NO reconsider for any marks given• NO empty-talk in my class• NO delay assignments submitting• NO inappropriate wear• NO hang around in my class• NO stupid talk