Centre of Diploma Studies Page 1/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester II CENTRE OF DIPLOMA STUDIES COMPUTER AIDED DESIGN LABORATORY LABORATORY INSTRUCTION SHEETSubject’s Code DEE 2213 / DAE 21503Experiment’s Title DC ANALYSISCourse’s Code 2 DEE/DET/DAENo. of Experiment 4
Centre of Diploma Studies Page 2/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester IIAIM: To provide understanding in DC transfer characteristic.1.0 OBJECTIVES 1. To be able to the DC Sweep mode of operation. 2. To be able to use markers for convenient trace variable display.2.0 OVERVIEW The DC sweep analysis causes a DC sweep to be performed on the circuit. DC sweep allows you to sweep a source (voltage or current), a global parameter, a model parameter, or the temperature through a range of values. The bias point of the circuit is calculated for each value of the sweep. This is useful for finding the transfer function of an amplifier, the high and low thresholds of a logic gate, and so on. R 1 Vd 1k V V1 0Vdc D 1 D 1N 914 0 0 DC sweep for the above figure is to analyze the voltage barriers for diode 1N914 as source voltage, V1 varies from -15V to 15V. Normally, plotted graphs depend on type of analyses used. In this case x-axis is voltage source variations and y-axis is diode voltage, as in figure below. 5V 0V - 5V - V 10 - 15V - 15V - V 10 - 5V 0V 5V 10V 15V V D) (V V 1 _V
Centre of Diploma Studies Page 3/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester IITo check diode voltage barrier, plotted graph should be I(diode) vs V(diode). Tochange x-axis into I(diode), select Axis setting → X-axis → Axis Variable, and selectdiode current. I(diode) vs V(diode) graph should be as figure below. 5V 0V - 5V - V 10 - 15V 0A 2mA 4mA 6mA 8mA 10mA 12mA 14mA 16mA V D) (V I(D1)PSpice allows one to vary a parameter and to evaluate its effects on the dc analysis.The parameters could be a circuit element such as R, L, C and their model parameter.The sweep variable name can be one of the following:Source. A name of an independent voltage or current source. During the sweep, thesource’s voltage or current is set to the sweep valueModel parameter. A model type name and then a model name followed by a modelparameter name in parenthesis. The parameter in the model is set to the sweep value.Temperature. The keyword TEMP followed by the keyword LIST. The temperatureis set to the sweep value. For each value of sweep, the model parameters of all circuitcomponents are updated to that temperature.Global parameter. The keyword PARAM followed by a parameter name. Theparameter is set to sweep. During the sweep, the global parameter’s value is set to thesweep value and all expressions are evaluated.
Centre of Diploma Studies Page 4/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester II3.0 EQUIPMENT LIST: 1. Personal Computer 2. OrCAD Capture CIS 3. OrCAD Pspice A/D 4. Storage Device4.0 PROCEDURE: 1. Reconstruct circuit in Figure 4.1 into PSpice equivalent circuit. a. Print out the PSpice equivalent circuit diagram. b. Sweep the current source from 0A to 3A with 0.1A increment. c. Plot power delivered at 8Ω resistor d. Get the power delivered when current is at 1.8A e. Print out graph from (d). f. Add another plot window to trace V(in) vs V(load). g. Get the value of V(load) when V(in) is at 10V. h. Print out graph form (g). in load 2 + I12 A V1 V1 A 4 4 8 - Figure 4.1 Important Note: When assigning the gain in dependent source, ensure it is in decimal form instead of fractional form ( e.g : set gain to 0.25 instead of 1/4)
Centre of Diploma Studies Page 5/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester II 2. Construct circuit as in Figure 4.2: a. Print out the Pspice equivalent circuit b. Replace the RL resistor with the suitable model for parametric analysis. c. Sweep the RL from 1Ω to 30Ω with 1Ω increments. d. Plot the power (watt) dissipated in RL. e. Get the maximum power dissipated by RL. f. Print out graph from (e). g. Get the value of Thèvenin Resistance (RTH) with RL as output terminal. h. Print out output file for (g). 4 12 i1 V1 3i1 V 3V R L Figure 4.25.0 ANALYSIS 1. From graph 4.1e; what is the power delivered at 8Ω when input current is at 1.8A. (3 marks) 2. What is V(load) value accumulated form graph from graph 4.1h. (3 marks) 3. Make a conclusion from plotted graph in procedure 4.1h. (3 marks) 4. Make a conclusion from graph 4.2e. (4 marks) 5. From 4.2h, get the Thèvenin equivalent circuit. (4 marks) 6. From 5.5, calculate total current during maximum power dissipation of RL. (3 marks)
Centre of Diploma Studies Page 6/6 Electrical Engineering Department Session 2010/2011 Experiment’s Title: DC Analysis Semester II6.0 DISCUSSION 1. Discuss dc analysis (.DC) in general. (5 marks) 2. Discuss how dependent sources are translated into PSpice equivalent circuit in this exercise. (5 marks) 3. Discuss parametric analysis in general. (5 marks) 4. Discuss two methods introduced in this experiment in determining maximum power dissipation. (5 marks)7.0 CONCLUSION Make a conclusion form the listed topics. 1. DC analysis (.DC) simulation for electrical circuit. (5 marks) 2. Independent and dependent sources adaptation in PSpice equivalent circuit. (5 marks) 3. Parametric analysis (.PARAM) simulation for electrical circuit. (5 marks)8.0 REPORT WRITING Report writing can be written in English or Malay. Report writing must be handwritten and submitted at the end of lab session. Report can be submitted in a group of two. Group reporting consists of individual results (print out), individual analysis, group discussion and group conclusion.