(SEM-III) THEORY EXAMINATION 2022-23 DIGITAL SYSTEM DESIGN

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