Digital Systems (CY-304) - Important Questions

Convert base-7 to decimal/hexadecimal, decimal to octal/base-4, hexadecimal to octal/binary, and find 9's and 10's complement.

Represent the decimal number 6 in Excess-3, BCD, Gray, 84-2-1 and 2421 codes.

Simplify $F(w,x,y,z) = y'z' + w'x'z' + w'xyz' + wyz'$ and implement the simplified result using universal gates only

Convert given numbers between various bases and codes (binary, octal, decimal, hexadecimal, Gray, BCD, Excess-3).

Simplify a given SOP Boolean function using K-map.

Implement a given Boolean function using only NAND gates

Express the Boolean function $F(x,y,z) = (xy+z)(y+xz)$ as a sum of minterms and as a product of maxterms.

Express Boolean function $F(x,y,z) = (xy+z)(y+xz)$ as sum of minterms and product of maxterms

Minimize a 4-variable Boolean function given as sum of minterms (with or without don't cares) using K-map and implement the minimal expression using logic gates.

Add decimal numbers in BCD and convert base-7 number to base-12.

Express the Boolean function $F = xy+z$ in product of maxterms form and explain BCD addition correction when the sum exceeds 9.

Explain how all basic gates can be realized using only NOR gates

What is a multiplexer, its role, and how it selects one input among several inputs, including $8{:}1$ multiplexer with truth table and expression.

Write a short note on decoder.

Draw a full subtractor circuit using NAND gates.

Implement a given Boolean function using a multiplexer such as $4{:}1$, $8{:}1$ or $16{:}1$ MUX.

What is an encoder? Design and explain a decimal-to-BCD encoder.

Explain the working of a full adder with truth table and logic diagram and its need in arithmetic circuits.

Design and explain the working of a Full Adder with truth table and logic diagram.

Implement a given Boolean function using a 4:1 multiplexer with specified select variables.

Design a Half adder circuit with truth table and logic diagram.

Implement given Boolean functions $F_1, F_2$ using a decoder and external gates.

What are the different types of parallel adders? Explain carry save and carry look-ahead adders.

Explain the BCD-to-decimal decoder

Explain the working of the master-slave J-K flip-flop.

Describe the 4-bit universal shift register with a neat diagram.

Explain race-around condition in J-K flip-flop and how master-slave configuration removes it.

Design a ripple decade counter using JK flip-flops.

Write a short note on PLA.

Explain asynchronous (ripple) counters and synchronous counters and compare them with respect to speed and hardware complexity.

Implement the given Boolean functions using PLA and draw the PLA programming table.

Design a 3-bit/4-bit binary UP/DOWN counter with direction control using T flip-flops, with timing diagram.

Show how the J-K flip-flop can be operated as a toggle flip-flop.

Compare the architectures of PLA, ROM, and PAL.

Explain DRAM and FLASH RAM.

Explain: Coincident selection addressing.

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

Explain the need for interfacing between TTL and MOS logic and how TTL-to-MOS/CMOS interfacing is achieved.

Explain the principle and working of a sample and hold circuit with diagram and its need in ADC systems.

Explain the internal block diagram and working of the IC 555 timer and discuss two applications.

Draw the circuit diagram of a Schmitt trigger and explain its working.

Describe the circuit, performance and characteristics of a CMOS inverter.

Draw and explain the working of a sample and hold circuit with neat diagram, including why it is required in ADC systems.

Explain the working of a Schmitt trigger circuit with a neat diagram and design it for $V_{UT} = 2\text{V}$, $V_{LT} = -1\text{V}$ with $+V_{sat} = +13\text{V}$, $-V_{sat} = -13\text{V}$.

For an 8-bit D/A converter with resolution $10\text{ mV/bit}$, find the analog output voltage for given binary inputs.

Explain the need for interfacing between TTL and CMOS/MOS logic and describe the interfacing techniques.

Draw and explain PMOS, NMOS and CMOS logic families.

Explain the working of a Schmitt trigger with a neat diagram and design it for given upper and lower threshold voltages and saturation voltages.

Explain the concept and working principle of Time Division Multiplexing (TDM) with block diagram, including multiplexing basics and synchronous vs asynchronous TDM.

Explain the quantization process and quantization error/noise in PCM and how quantization noise can be reduced.

Explain the Pulse Code Modulation (PCM) system with a neat block diagram.

Explain the geometrical / signal-space representation of non-orthogonal BFSK.

Explain mutual information and its relation to channel capacity, and compute the Shannon limit in bits/sec for a voice-band channel with given SNR and bandwidth.

Explain the PCM system with its block diagram

Define mutual information, relate it to channel capacity, and compute the Shannon limit for a voice-band channel with given SNR and bandwidth.

Explain the BFSK modulation scheme and its working.

What are logic gates? Describe the different types of logic gates.