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Questions tagged [digital-circuits]

Digital circuits use logic gates as the basic building block. A logic gate performs a logical operation on binary inputs and produces a single binary output. The Primary Logical operations are AND (conjunction), OR (disjunction) and NOT (negation).

Use this tag when discussing about the design, simulation and verification of digital circuits. To learn more about digital circuits visit:

Digital Electronics on Wikipedia

102 questions
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Trick/insight to I implement given boolean function with minimum numbers of given gate

I solved bunch of questions which give some function and then ask to implement it with minimum number of gates of specific type, each having specific number inputs. I was making mistakes in all those problems by not implementing given function with…
RajS
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General Approach To Calculate Minimum Number Of Flip-Flops Required

In the previous two years of the GATE exams, a question has been asked for finding number of flip flop's for counting sequence $0−1−0−2−0−3$ in 2016 and $0−0−1−1−2−2−3−3−0−0$ in 2015. But still, the approach discussed in these questions hasn't…
Akhil Nadh PC
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Physical significance of Don't cares in Digital Logic design

In many Digital functions we come across don't care conditions where we use don't cares to minimize functions. What is the significance of these don't cares in real world scenario where we actually implement the functions using logic gates?
Ashutosh
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What is the behavior of the given counter?

I found the following question - For the circuit shown in the figure, the delay of the bubbled NAND gate is 2ns and that of the counter is assumed to be zero If the clock (Clk) frequency is 1GHz, then the counter behaves as a (A) mod-5 counter…
Mr. Sigma.
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How many possible prime implicants are there in total for a 4-variable Karnough-map?

The answer for this question is 81. But I count figure out why. Can someone explain to me how does this work. Thank you.
user10024395
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Difference between end carry and overflow

I am confused with end carry and overflow. When will an end carry be the overflow? How to identify whether the end carry is overflow or not? Are they both same? Sometimes end carries obtained are simply discarded and sometimes the end carries are…
hanugm
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Carry Look Ahead Adder for stabilize the sum

An four-bit carry-look-ahead adder for computing the sum of 2 numbers , where A and B are integers represented in 2's complement form. If the decimal value of A is 3, the decimal value of B that leads to the longest value for the sum to stabilize is…
Mark
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Logic Gates in circuits

We can make all the gates using nand or nor gates. My teacher told us that nand gates are cheap too, then why do we need other gates at all?
Aniswar S K
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At what point do electrical signals become actually logic and programmable language?

I get that one transistor can store a value of 1 or 0. That's not the problem. What I don't get is how the fact that a transistor represents a 0 can translate into logic? How do these transistors turn each other one or of? Is there a uniform pattern…
TinkerTek
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Addition of 3 bits using Full Adder when the initial carry bit is 0

How do I add 3 bits using full adder and basic gates, when the initial carry bit is 0?? I have tried using two full adders where two terminals of the first adder gets the first two inputs then the output of this adder goes to of the inputs of the…
ATM_shifat
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How to calculate the output frequency of this counter?

The present state Q2,Q1,Q0 of the counter before applying the clock pulse was (101). If the input Clock frequency to the circuit is 100KHz, then the output frequency of the circuit will be ? My Approach: I have built the state table and I concluded…
Sanjay Verma
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two laws of De Morgans law and its used as NAND gates and NOR gates

how the all gates can be made by only these two . Yes i know the circuit diagram of basic gates by universal gates which i have learnt. but if there is complex circuit like XOR gate or any other expression how would you make it please upload some…
Akshay Kathpal
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