The document is an exam paper for an Analog Electronics II course. It consists of 5 questions testing knowledge of operational amplifiers, feedback, amplifier classes, multivibrators and oscillator circuits.
The document is an exam paper for an Analog Electronics II course. It consists of 5 questions testing knowledge of operational amplifiers, feedback, amplifier classes, multivibrators and oscillator circuits.
The document is an exam paper for an Analog Electronics II course. It consists of 5 questions testing knowledge of operational amplifiers, feedback, amplifier classes, multivibrators and oscillator circuits.
The document is an exam paper for an Analog Electronics II course. It consists of 5 questions testing knowledge of operational amplifiers, feedback, amplifier classes, multivibrators and oscillator circuits.
DEPARTMENT OF ELECTRICAL AND ELECTRONIC ENGINEERING
CERTIFICATE IN ELECTRONICS
ANALOGUE ELECTRONICS II
END OF SEMESTER EXAMINATIONS
SERIES: AUGUST/SEPTEMBER 2011
TIME: 2 HOURS
Instructions to Candidates: You should have the following for this examination Answer booklet Drawing instruments Scientific calculator This paper consists of FIVE questions Answer question ONE (COMPULSORY) and at least THREE other questions
Maximum marks for each part of question are clearly indicated This paper consists of THREE printed pages Question 1 (Compulsory)
a) (i) state FOUR properties of an ideal operational amplifier
(ii) Define the term slew-rate and C.M.R.R as used in ‘op-amps’ (8 marks)
b) Draw and explain the frequency response curve of an RC compled CE amplifier
(6 marks) c) (i) State THREE advantages of negative feedback as used in amplifiers (ii) State any TWO advantages and TWO disadvantages of RC compled amplifier (6 marks) d) With the aid of diagrams, explain the operation of class AB push-pull power amplifier (10 marks)
Question 2 a) State: i) Any TWO causes of drift in DC amplifier ii) Any TWO methods of reducing it (4marks)
b) Draw the circuit diagram of a Darlington pair amplifier and show that its gain is give by 2 (14 marks) c) Draw a characteristic curve for a DC amplifier (2 marks)
Question 3
a) With the aid of diagrams, explain how you can
i) ‘null’ an op-amp ii) Determine common-mode gain (10 marks)
b) Design an adder circuit using an ‘op-amp’ to get the output expression as
Vo = - (0.1V1+V2+10V3)
Where V1, V2 and V3 are input voltages
Assume Rf = 10k (10 marks)
Question 4
a) With the aid of diagrams, explain the following classes of amplifier operations: i) Class A ii) Class B (10 marks)
b) With the aid of diagrams, explain how distortion occurs in class B amplifier and state its possible remedy (10 marks)
a) (i) Differentiate between a stable multivibrator and unstable multivibrator (3 marks)
(ii) With the aid of diagrams, explain the operation of an a stable multivibrator (10 marks) b) Explain the meaning of the following terms (i) Damped oscillations (ii) Undamped oscillations (4 marks)
c) Explain how to convert damped oscillations to undamped oscillations (3 marks)
