RTU Kota BTech 3rd Semester Digital System Design Question Paper 2026 (ECE and BI)

RTU Digital System Design 2026 Paper Review

Preparing for the Rajasthan Technical University BTech Digital System Design exam requires a firm grasp of binary logic, circuit simplification, and hardware architecture. For Electronics and Communication or Biomedical Engineering students designing medical instrumentation or communication hardware, understanding how logic gates control electrical signals is foundational. You cannot build functional digital hardware without understanding truth tables, state machines, and propagation delays.

The 2026 paper tests your capability to minimize Boolean expressions, design synchronous counters, and implement logic functions using programmable hardware. Publishing this specific 3rd semester paper review directly to your exam support website provides your users exactly what they need to understand how examiners construct hardware design problems and distribute marks across logic families. This targeted preparation strategy helps approach the exam confidently, Aryan.

Understanding the Exam Pattern

The RTU theory examination is a three hour paper worth 70 marks. The paper features three distinct sections designed to evaluate both basic logic definitions and complex circuit designs.

Part A: This section contains ten compulsory questions worth two marks each. You must define terms like noise margin, state De Morgan theorems, define a multiplexer, or explain the difference between a latch and a flip flop under 30 words.

Part B: You will find seven questions here. You must answer five of them. Each question is worth four marks. Your answers require explaining the operation of a master slave flip flop, converting a specific binary number to Gray code, or differentiating between static and dynamic RAM with examples.

Part C: This section offers five major questions. You need to answer three. Each question carries ten marks. These require you to minimize a four variable Boolean function using a Karnaugh map, design a modulo 10 synchronous counter using JK flip flops, or detail the internal architecture of a Field Programmable Gate Array.

Core Topics Evaluated in the Paper

The 2026 question paper covers several critical modules that establish the mathematical rules for digital hardware. Focus your study time on these specific areas to maximize your score.

Number Systems and Boolean Algebra

This module evaluates your understanding of binary arithmetic and logic simplification. You must master base conversions and binary codes like BCD and Excess 3. Practice minimizing complex Boolean expressions using both algebraic methods and Karnaugh maps. Understand how to apply Quine McCluskey tabulation for functions with five or more variables. For example, you must be comfortable minimizing a sum of products expression like:

$$F(A,B,C,D) = \sum m(0, 1, 2, 5, 8, 9, 10)$$

Combinational Logic Circuits

Combinational circuits generate outputs based entirely on current inputs. You must master the design of adders, subtractors, multiplexers, and decoders. Practice drawing the logic diagrams for a carry lookahead adder. Understand how to implement a specific Boolean function using only universal gates like NAND or NOR.

Sequential Logic Circuits

This module focuses on circuits with memory. You must understand how clock signals trigger state changes. Study the excitation tables for all standard flip flops. The paper heavily features design problems requiring you to construct state transition diagrams, build state tables, and derive the final logic circuit for both synchronous and asynchronous counters.

Logic Families and Memory Devices

Review the electrical characteristics of different logic families. You must compare Transistor Transistor Logic and Complementary Metal Oxide Semiconductor families based on power dissipation and propagation delay. Understand the architecture of Read Only Memory and Random Access Memory. Study the structural differences between Programmable Logic Arrays and Programmable Array Logic.

Answer Writing Strategy for High Marks

RTU evaluators look for clean circuit diagrams, explicitly stated truth tables, and clear derivation steps. Use a blue pen for text explanations and Boolean algebra. Use a black pen and ruler for drawing logic gates, block diagrams, and timing signals.

In Part A, answer directly. If a question asks for the definition of fan out, state clearly that it is the maximum number of standard logic inputs that an output can drive reliably.

In Part B, use clear graphical structures. When explaining a half adder, draw the truth table and quickly sketch the XOR and AND gate implementation to visually prove the logic.

In Part C, precision in design is critical. When solving a ten mark counter design problem, draw the complete state diagram first. Write the excitation table clearly, and explicitly show the Karnaugh map groupings for each flip flop input. If you derive the final equations, draw the complete logic circuit connecting the clock inputs properly.

Time Management During the Exam

Allocate exactly 20 minutes to Part A. Spend 40 minutes addressing the five short answer questions in Part B. Reserve the remaining 120 minutes for the three long answer questions in Part C. Drawing extensive logic circuits, constructing large truth tables, and mapping multi variable Karnaugh maps requires steady focus and significant writing time. This distribution guarantees you 40 minutes per major question, giving you time to double check your Boolean minimizations. Use the final 10 minutes to verify your question numbering, ensure all gate inputs connect to the correct signal lines, and check that your truth table outputs match the problem requirements.