EE106 Analog Electronics Exam Instructions & Questions for Summer Exams 2008/2009, Exams of Electronics

Download EE106 Analog Electronics Exam Instructions & Questions for Summer Exams 2008/2009 and more Exams Electronics in PDF only on Docsity! EE106 Analogue Electronics Page 1 of 7 Summer Examinations 2008/ 2009 Exam Code(s) 1BN, 1BP, 1BEE Exam(s) 1 st Electronic Engineering 1 st Electronic & Computer Engineering 1 st Sports and Exercise Engineering Module Code(s) EE106 Module(s) Analogue Electronics Paper No. 1 Repeat Paper No External Examiner(s) Professor George Irwin Internal Examiner(s) Professor Gearóid ÓLaighin Mr. Gavin Corley Dr. Edward Jones Instructions: Answer all of question 1 and any 2 other questions. Question 1 is compulsory and carries 40 marks. Choose 2 questions from questions 2, 3 and 4. Each question carries 30 marks. Duration 2 hours No. of Pages 7 Department(s) Electrical & Electronic Engineering Course Co-ordinator(s) Gavin Corley Requirements: MCQ Handout Statistical Tables Graph Paper Log Graph Paper Other Material Standard Mathematical Tables EE106 Analogue Electronics Page 2 of 7 Question 1 is compulsory 1. (a) For the circuit shown in Figure 1.1 calculate: (i)The total resistance of the circuit, RT [2 marks] (ii)The value of the resistor, R [3 marks] Figure 1.1 1. (b) (i) State Kirchhoff’s Current Law. [1 mark] (ii) State Kirchhoff’s Voltage Law. [1 mark] (iii) For the circuit shown in Figure 1.2 calculate the values of resistors R1 and R2. [3 marks] Figure 1.2 1. (c) From the pulse waveform shown in Figure 1.3 calculate: (i) The frequency (f) of the waveform. [1 mark] (ii) The period (T) of the waveform. [1 mark] (iii) The rise time of the waveform. [1 mark] (iv) The fall time of the waveform. [1 mark] (v) The pulse width of the waveform [1 mark] Figure 1.3 EE106 Analogue Electronics Page 5 of 7 2. For the circuit of Figure 2: (a) State the Principle of Superposition. [4 marks] (b) Calculate the current flowing in the 15Ω resistor due to the 9V voltage source. [7 marks] (c) Calculate the current flowing in the 15Ω resistor due to the 3A current source. [7 marks] (d) Calculate the current flowing in the 15Ω resistor due to the 24V voltage source. [7 marks] (e) Using the principle of superposition, calculate the total current and power dissipated in the 15Ω resistor. [5 marks] Figure 2 EE106 Analogue Electronics Page 6 of 7 3. (a) (i) Determine the Thévenin equivalent of the circuit inside the box of Figure 3 (without the load circuit attached). [12 marks] (ii) Proceed to draw the Norton equivalent of the same circuit [4 marks] (iii) Derive an expression for the total resistance of the load circuit shown on the right of Figure 3. Proceed to determine what value of R will lead to the maximum power being delivered to the load circuit. [4 marks] Figure 3 (b) Explain (a) the formation and (b) the operation of a p-n junction diode using the following terms: doping, depletion region, barrier voltage, forward bias, reverse bias and breakdown voltage. [10 marks] EE106 Analogue Electronics Page 7 of 7 4. (a) The circuit of Figure 4 shows a series connected RLC circuit. (i) Explain the concept of electrical resonance in this circuit. [4 marks] (ii) Calculate the resonant frequency of this circuit. [8 marks] (iii) Draw a phasor diagram showing the impedances, R, XL and XC of this circuit. [5 marks] (iv) Calculate the total impedance of the circuit. [3 marks] Figure 4 (b) A smoothing capacitor is to be added to a half wave rectifier circuit with input: v(t) = 10sin(120πt) and load resistance RL = 3kΩ. (i) Calculate the value of the capacitance necessary in order to keep the ripple of the output voltage below 10%. [6 marks] (ii) Plot two cycles of the smoothed output voltage waveform. Give an approximate value for the average output voltage when the smoothing capacitor is attached. [4 marks]