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Questions tagged [truth-table]

A truth table is a mathematical table used in logic—specifically in connection with Boolean algebra, boolean functions, and propositional calculus—which sets out the functional values of logical expressions on each of their functional arguments, that is, for each combination of values taken by their logical variables.

A truth table is a mathematical table used in logic—specifically in connection with Boolean algebra, boolean functions, and propositional calculus—which sets out the functional values of logical expressions on each of their functional arguments, that is, for each combination of values taken by their logical variables (Enderton, 2001). In particular, truth tables can be used to show whether a propositional expression is true for all legitimate input values, that is, logically valid.

A truth table has one column for each input variable (for example, P and Q), and one final column showing all of the possible results of the logical operation that the table represents (for example, P XOR Q). Each row of the truth table contains one possible configuration of the input variables (for instance, P=true Q=false), and the result of the operation for those values.

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What are the names of all possible logic gates with 1-or-2-bit input and 1-bit output?

This seems to be a silly question, but the fact is that when I tried to search for related information, none of the search results gave me satisfactory answer. Logic Gates with 1-bit Input and 1-bit Output Since the input has \$B=1\$ bit, the truth…
Siu Ching Pong -Asuka Kenji-
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How do you cascade two 7-segment decoder ICs together?

We used one 74LS47 IC in our lab, which we connected to a 7-segment display and tested the outputs. Now our instructor has told us to cascade two 7447 ICs together and implement it on a 7-segment display. Also, the instructor did not show us how to…
Bukharian1776
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If two Boolean functions \$f_1\$ and \$f_2\$ have same truth table, does that means they have exactly same characteristic? can one f1 numerate to f2?

if \$f_1(x,y,z)=\neg xz+x\neg y+\neg xy\neg z+xy\neg z\$ determine if \$f_1\$ is symmetric and whether it is unate. What I thought is: \$f_1\$=¬xz+x¬y+y¬z, the truth table of \$f_1\$ has the same truth table with the function \$f_b = x\oplus \neg…
gobears21
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How are LUTs in a FPGA filled?

I know there have been a lot of questions about lookup tables and their design, but even after reading them and scouring the web, I still don't quite understand how the LUTs are filled with corresponding boolean function's outputs from SRAM. What…
Lokwill
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Name for this logic operation

I'm from math.stackexchange and I wanted to know the name of an operation on multiple variables. I thgouth what I wanted was the XOR gate, but this is not the case. When I looked on this site I noticed the XOR truth table was this: \begin{matrix}…
Ben Crossley
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Did I create this Karnaugh map correctly?

I'm tasked with making a 4-7 decoder for a 7-segment LED (common anode). I am an extreme layman (1st year EEE student) I have 4 inputs (A,B,C,D) A inputs are: 0000000011111111 B inputs are: 0000111100001111 C inputs are: 0011001100110011 D inputs…
NonComposMentis
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Will the Karnaugh diagram change when you use gray code on the truth table?

I am currently trying to put this state diagram into a truth table: I wrote the truth table like this: When I try to get the expression for q1+ I get: q1+ = q1q0' + q1q0x, but I can apparently get: q1+ = q1q0 + q0*x Do you setup the K-map…
Zeptuz
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Writing Truth Table Given Function

so I am taking a summer course and the teacher is not so helpful at the moment so I was thrown the following question to do: Derive a truth table for the following function: \$f(x,y,z)=\sum m(1,3,5,7)\$ I dont know how to interpret the equation to…
John Rettiner
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How can I draw the diagram using few decoders for this truth table?

For the truth table above, abc is the input and xyz is the output. I do know how to draw the diagram using a decoder in case of when I have only one output. How can I draw the diagram using a decoder when I have 3 outputs for this case? This is…
Sangmin Choi
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Addition and subtraction of binary digits

I have to solve the following exercise : Extend the circuit of the first part (the first part was an adder of integer numbers of 2 binary digits) in order to execute addition and subtraction of integers numbers of 2 binary digits (AB+-CD).…
Deppie3910
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Transition table from state truth table

Assuming a simple binary state variable allocation can be made and that any unused states can be treated as don’t cares. How would I Design a corresponding transition table for this system including flip-flop (D- FF) inputs and system…
Emoanimelovr
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Query regarding 9 V battery connection to 7408 IC

I have got some LEDs, a breaboard, a 74HC08 IC, a 9 V battery, resistors of 10 and 100 ohms. I want to check the IC by connecting it to a breadboard but the IC input voltage is 5 V and current 8 mA. On calculation I found that if I connect around…
Arjun Kumar
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7-segment display decoder truth table

I am trying to make a decoder that can display all alphabetical letters on a 7-segment display. My inputs are ABCDE and the outputs are abcdefg Is this the correct truth table for a circuit? If yes, what would its transformation to normal form look…
Elias Al Ahmar
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Difference between waveform and truth table

Is there a difference between waveform and truth table to represent the values of a circuit? For example: Are there particular cases where one or the other should be used?
Ricardo Casimiro
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Convert boolean expression to nand gate only. X = A'B'C+AB'C'+A'B'

I have already made a diagram. However, it won't match the truth table that I have made, which I got from the logic converter in multisim. Could you please help me out with where did I go wrong? Is it on my diagram or in my truth table?
trese
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