Digital Electronics Logic Design (EX-403) - Important Questions

Convert numbers between decimal, binary, octal and hexadecimal, including fractional parts.

Explain parity generators and checkers / write short notes on parity generators and checkers

Using the tabular (Quine-McCluskey) method with don't cares, find the prime implicants/implicates and obtain the minimal sum-of-products expression for the given Boolean function.

State and prove De Morgan's theorems and convert $(A5D8)_{16}$ to BCD.

Simplify a 5-variable logic function $Y=\Sigma m(0,2,3,4,6,7,9,11,16,18,19,20,22,23,25,27)$ using K-map.

Using the tabulation (Quine-McCluskey) method, obtain the simplified minimal expression in product-of-sums (POS) form for the given Boolean function.

Explain the error detection using parity method in digital transmission. Discuss how odd parity error detection carried out for transmitting the letter 'B' in ASCII code.

A line printer is capable of printing 132 characters in a single line and each character is represented by ASCII code. How many bits are required to print each line?

Simplify/minimize a 4-variable Boolean function in SOP form $\Sigma m$ (with don't-care conditions $d$ where given) using K-map and implement with logic gates.

Convert given numbers in hexadecimal, octal and decimal to binary and then to Gray code.

Demonstrate De Morgan's theorems for three variables by truth tables and find complement of $F = a(b'c'+bc)$ using De Morgan's theorem.

Convert numbers between decimal, binary, octal and hexadecimal including binary to Gray code conversion.

Implement a 4-variable Boolean function $F(A,B,C,D)=\Sigma m(\dots)$ using an 8:1 multiplexer.

Write short notes on any two topics including priority encoder, decoding in counter, programmable logic devices (PLA/PAL) and data converters.

Explain half subtractor with truth table and logic circuit design.

Explain why NAND and NOR gates are called universal gates and realize NOT, AND, OR, XOR, XNOR gates using NAND and/or NOR gates.

Draw and explain the look-ahead carry generator/adder and explain why it is faster than a ripple carry adder.

Implement a full adder using only NAND gates.

What do you understand by decoder? Design a binary to Gray code Decoder.

What is a magnitude comparator? Design a 2-bit magnitude comparator.

Explain the need for a full adder and design a full adder (and half adder) with truth table and logic circuit diagram.

Design / implement a full adder using two half adders and an OR gate with circuit diagram.

Give the general procedure with example for converting a multilevel AND-OR diagram into an all-NAND diagram.

Realize the Boolean expression $Z = ABC + AD + CD'$ using only NAND gates.

Explain the operation of a positive edge-triggered D flip-flop with circuit diagram and waveforms.

Explain the working/operation of a JK flip-flop with circuit diagram and truth table.

Explain the working principle of Master-Slave flip-flop with circuit diagram and truth table.

Design a 2-bit controlled sequential circuit with input $x$ where $x=0$ holds state and $x=1$ cycles through $00 \to 01 \to 11 \to 10 \to 00$.

Define the following and explain:

Write the logical equations and construct the transition table for a sequential circuit in terms of inputs and secondary variables.

Convert an SR flip-flop to a JK flip-flop.

What is Latch? What are the difference between Latch and Flip Flop? Explain D latch with truth table and logic diagram.

Derive the state table and state diagram for a given sequential circuit.

Explain race-around condition in JK flip-flop with diagram and how it is removed by Master-Slave configuration.

Prepare the state table and excitation table for a given sequential machine using T flip-flop.

Differentiate latch vs flip-flop and analyze a synchronous sequential circuit from given JK input equations to obtain logic diagram, state equations, state table and state diagram.

Draw and explain the working of a Johnson counter.

Explain the operation of a 4-bit bidirectional / universal shift register with parallel load using a diagram.

Design a synchronous binary (mod-8 / 4-bit) counter using flip-flops and explain its working with timing diagram.

Explain UP and DOWN / up-down counters including 4-bit synchronous up-down binary counter and applications of counters.

Explain what is a counter and the working of a ring counter with suitable diagram.

Explain registers and the operation of shift-right and shift-left shift registers with diagrams.

Design a MOD-7 (0 to 6) synchronous counter using JK flip-flops.

Design a synchronous irregular-sequence counter using JK flip-flops for the sequence 0-1-2-4-5-6-0.

Draw a 4-bit asynchronous UP (ripple) counter, discuss its characteristics and draw its waveforms.

What are the different types of registers? Explain the Parallel Input Serial Output shift register.

Compare asynchronous (ripple) and synchronous counters, including characteristics like propagation delay, lockout, and applications.

Write about ring counter and universal shift registers.

Explain the principle of operation / working of a successive approximation ADC.

Explain what Read-Only Memory (ROM) is and describe its different types.

Explain memory decoding. How long will it take to erase UV erasable EPROM completely?

Explain about Read and Write cycles of a static RAM with neat timing waveforms.

Implement the given Boolean functions $W, X, Y, Z$ using PAL.

With a neat diagram explain in detail about two dimensional memory decoding scheme.

Implement given Boolean functions using a PLA with specified inputs, product terms and outputs.

What are sequential programmable devices? Draw and explain the sequential programmable logic of a basic microcell.

Realize a full adder circuit using PAL.

Draw the basic circuit of a ROM cell and explain its working.

Explain the operation of an R-2R ladder DAC with a neat diagram.

Write short notes on De-Morgan's theorem, RAM, and PLA and PAL.

Write a short notes on any Two: