About this previous year paper
This question paper covers the core concepts, problem-solving techniques, and design principles of Digital Electronics and Logic Design, intended for undergraduate engineering students. It evaluates a student’s understanding of number systems, Boolean algebra, combinational and sequential circuit design, logic simplification, flip-flop behavior, counters, decoders, multiplexers, DAC/ADC circuits, and Programmable Logic Devices (PLDs).
The paper is divided into three structured sections, ensuring a balanced assessment of theoretical knowledge, analytical skills, and circuit-design ability:
SECTION A – Short Conceptual Questions (20 Marks)
This section consists of 10 brief questions, each designed to test fundamental concepts. Students must define terms, explain principles, and distinguish between closely related digital electronics concepts such as minterms, maxterms, race-around condition, ADC types, fan-in/fan-out, and TTL/CMOS characteristics.
SECTION B – Descriptive / Design Questions (30 Marks)
Students must attempt any three of the given design-oriented and analytical questions.
Topics include:
Single-bit magnitude comparator design
NAND-only implementation methods
R-2R DAC construction and working
Universal shift register design
Totem-pole TTL NAND gate operation
These questions test deeper understanding, circuit interpretation skills, and the ability to apply principles to real hardware-level design.
SECTION C – Long Answer / Application-Based Questions (30 Marks)
This section contains four sets of two-part questions, out of which one part from each set must be attempted.
It includes:
K-map simplification
MUX-based logic implementations
Ripple counter design
Dual-slope ADC explanation
Tabular method minimization
Weighted-resistor DAC
Decoder and ROM-based logic implementation
Sequential circuit design
CMOS inverter working
PLA-based circuit implementation
These questions require analytical thinking and practical digital system design capabilities.
Purpose of This Examination
This exam is structured to ensure that students can:
Understand number systems, logic functions, and Boolean algebra
Analyze and design combinational & sequential logic circuits
Implement digital logic using different platforms (gates, decoders, multiplexers, PLDs)
Demonstrate reasoning ability for optimization and simplification
Translate theoretical principles into real-world digital electronic systems