JNTU
JNTU B.Tech III LINEAR IC APPLICATIONS Previous Question Paper (January/February - 2023 - R15)
i) Question paper consists of Part A, Part B.
ii) Part A is compulsory, which carries 25 marks. In Part A, Answer all questions.
iii) In Part B, Answer any one question from each unit. Each question carries 10 marks and may have a, b as sub questions.
Part A
Define Common Mode Rejection Ratio (CMRR).
Answer
Common Mode Rejection Ratio (CMRR) is defined as the ratio of the differential-mode gain (Ad) to the common-mode gain (Ac) of an operational amplifier. It is a measure of the ability of the amplifier to reject common-mode signals and is typically expressed in decibels (dB) as CMRR = 20 log10 |Ad / Ac|.
What is the need for current mirror circuit in differential amplifiers?
Answer
A current mirror circuit is used in differential amplifiers to provide a stable, high-impedance constant current source for the emitter-coupled pair. This ensures that the total tail current remains constant regardless of variations in common-mode input voltage, thereby significantly improving the common-mode rejection ratio (CMRR) and providing high gain.
Draw circuit diagram for AC amplifiers using op-amp.
Answer
Sign in to view the complete answer paper.
How a practical differentiator circuit eliminates problem of instability?
Answer
Sign in to view the complete answer paper.
What are the disadvantages of passive filter?
Answer
Sign in to view the complete answer paper.
List the applications of sawtooth wave generator.
Answer
Sign in to view the complete answer paper.
Draw the block schematic of the PLL.
Answer
Sign in to view the complete answer paper.
State few applications of 555 timers.
Answer
Sign in to view the complete answer paper.
What are the limitations of weighted resistor type D/A converter?
Answer
Sign in to view the complete answer paper.
Calculate the value corresponding to LSB of 8 – bit DAC for 0 – 10 Volts range.
Answer
Sign in to view the complete answer paper.
Part B
With a neat internal block diagram, explain the importance of each internal block of an operational Amplifier.
Answer
Sign in to view the complete answer paper.
The output voltage of an op-amp circuit changes by 20V in 4micro seconds. Find the slew rate and derive the necessary equations.
Answer
Sign in to view the complete answer paper.
Explain the DC and AC analysis of Dual input Balanced output Differential Amplifier.
Answer
Sign in to view the complete answer paper.
With a neat circuit diagram and necessary waveforms explain op-amp as a:
Comparator
Answer
Sign in to view the complete answer paper.
Sample and hold circuit.
Answer
Sign in to view the complete answer paper.
With a neat circuit diagram, explain about voltage follower.
Answer
Sign in to view the complete answer paper.
Find R1 and Rf in the practical integrator (lossy integrator), so that the peak gain is 20 dB and the gain is 3 dB down from its peak when ω=10,000 rad/sec. Use a capacitance of 0.01 μF.
Answer
Sign in to view the complete answer paper.
Draw the square wave generator circuit using op-amp and derive the expression for frequency of oscillation.
Answer
Sign in to view the complete answer paper.
Design a wide band pass filter having fL=400Hz, fH=2KHz and pass band gain=4. Find the value of Q of the filter.
Answer
Sign in to view the complete answer paper.
Draw the circuit diagram of RC-phase shift oscillator and necessary derivations for frequency of oscillation.
Answer
Sign in to view the complete answer paper.
Draw the circuit of the Triangular wave generator using an op-amp and derive the expression for its Time period.
Answer
Sign in to view the complete answer paper.
Draw the block schematic of a PLL. And describe the function of each block briefly.
Answer
Sign in to view the complete answer paper.
Explain the operation of 555 Timer in an astable mode.
Answer
Sign in to view the complete answer paper.
Design 555 timer circuit in Astable mode to get output waveform with 50% duty cycle.
Answer
Sign in to view the complete answer paper.
Draw the complete block schematic circuit of a weighted resistor DAC and explain its operation. Derive expression for its output voltage for n-bits.
Answer
Sign in to view the complete answer paper.
An 8-bit analog to digital converter has a supply voltage of +12 volts. Calculate: (i) The voltage step size for LSB. (ii) The value of analog input voltage for a digital output of 01001011.
Answer
Sign in to view the complete answer paper.
Explain in detail the operation of a flash type of ADC
Answer
Sign in to view the complete answer paper.
Define important performance specifications of Digital to Analog converters and list their typical values.
Answer
Sign in to view the complete answer paper.