EC-405 RGPV B.Tech
Analog Circuits (AC)
Previous year papers and the official syllabus are free to read, no account needed.
Previous Year Papers
5 papers, latest Jun 2025
- EC-405 paper, Jun 2025
- EC-405 paper, Dec 2024
- EC-405 paper, Nov 2023
- EC-405 paper, Jun 2023
- EC-405 paper, Jun 2022
Syllabus, notes and important questions for EC-405
Syllabus units
Topics as the official RGPV syllabus lists them.
Unit 1 Feedback Amplifier and Oscillators 3 topics
- Concept of feedback and its types
- Amplifier with negative feedback and its advantages
- Feedback topologies
Unit 2 Oscillators 7 topics
- Concept of positive feedback
- Classification of oscillators
- Barkhausen criterion
- RC oscillator
- RC phase shift oscillator
- Wien bridge oscillator
- LC oscillators: Hartley, Colpitts, Clapp, and crystal oscillator
Unit 3 Introduction to Integrated Circuits 3 topics
- Advantages and characteristic parameters of ICs
- Basic building components of ICs
- Reading data sheets
Unit 4 Operational Amplifier 9 topics
- Differential amplifier analysis
- Dual‑input balanced‑output differential amplifier configuration
- Dual‑input unbalanced‑output differential amplifier configuration
- Single‑input balanced‑output differential amplifier configuration
- Single‑input unbalanced‑output differential amplifier configuration
- Introduction of op‑amp
- Block diagram of op‑amp
- Characteristics and equivalent circuits of an ideal op‑amp
- Power‑supply configurations for op‑amp
Unit 5 Characteristics of Op‑amp 13 topics
- Ideal and practical op‑amp behavior
- Input offset voltage
- Input offset current
- Input bias current
- Output offset voltage
- Thermal drift
- Effect of power‑supply voltage variation
- Common‑mode rejection ratio (CMRR)
- Slew rate and its effect
- Power‑supply rejection ratio (PSRR) and gain‑bandwidth product
- Frequency limitations and compensation
- Transient response
- Analysis of TL082 datasheet
Unit 6 Op‑amp Applications 31 topics
- Inverting amplifier configuration
- Non‑inverting amplifier configuration
- Summing amplifier
- Integrator circuit
- Differentiator circuit
- Instrumentation amplifier
- Differential input and differential output amplifier
- Voltage‑series feedback amplifier
- Voltage‑shunt feedback amplifier
- Log/antilog amplifier
- Triangular/rectangular wave generator
- Phase‑shift oscillator
- Wien bridge oscillator
- Analog multiplier (MPY634)
- Voltage‑controlled oscillator (VCO)
- Comparator
- Zero‑crossing detector
- Filter characteristics
- Classification of filters
- Magnitude and frequency response of filters
- Butterworth 1st‑order low‑pass filter
- Butterworth 2nd‑order low‑pass filter
- High‑pass filter
- Band‑pass filter
- Chebyshev filter characteristics
- Band‑reject filter
- Notch filter
- All‑pass filter
- Self‑tuned filters
- Automatic gain control (AGC) using op‑amp
- Automatic volume control (AVC) using op‑amp
Unit 7 Timer 15 topics
- IC‑555 timer concept
- Block pin configuration of timer
- Monostable multivibrator using 555
- Bistable multivibrator using 555
- Astable multivibrator using 555
- Schmitt trigger
- Voltage limiters
- Clipper circuits
- Clamper circuits
- Absolute‑value output circuit
- Peak detector
- Sample‑and‑hold circuit
- Precision rectifiers
- Voltage‑to‑current converter
- Current‑to‑voltage converter
Unit 8 Voltage Regulator 9 topics
- Simple op‑amp voltage regulator
- Fixed voltage regulator
- Adjustable voltage regulator
- Dual power‑supply regulator
- Basic switching regulator
- Characteristics of standard regulator ICs: linear regulator, switching regulator, low‑dropout regulator
- Study of LM317
- Study of TPS40200
- Study of TPS7250
Exam insights
Counted from 5 past EC-405 papers.
Marks asked per paper, by unit
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Unit 1 Feedback Amplifier and Oscillators 27 marks
-
Unit 2 Introduction to integrated circuits and Operational Amplifier 36 marks
-
Unit 3 OP-AMP applications 15 marks
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Unit 4 OP-AMP AS FILTERS 6 marks
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Unit 5 TIMER and Voltage Regulator 27 marks
Average marks of the questions from each unit in one paper. You answer only some of them, so the total is more than the paper’s maximum.
Asked again and again
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What is an integrated circuit (IC)? Explain its characteristics and relative advantages and disadvantages over discrete assembly.
Asked 5 times: 2024, 2023, 2022, 2019
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Define/explain op-amp DC and performance parameters: input offset voltage, input bias current, input offset current, output offset voltage, CMRR, PSRR, thermal drift, and their effect on accuracy
Asked 5 times: 2025, 2023, 2022, 2020, 2019
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Draw / sketch the RC phase-shift oscillator circuit, explain its working / operation and derive / determine the expression for frequency of oscillation.
Asked 5 times: 2024, 2023, 2020, 2019