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Questions tagged [logic-gates]

Symbolic representation of ideal devices implementing boolean functions

Logic gates are symbolic representation of ideal devices implementing boolean functions. See

Logic Gates Wikipedia Article

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OR gate vs. connecting two wires?

I am not much of an electrical person but I'm trying to get an idea about it, so keep in mind I have very little background outside of college level electrical physics with calculus, and a strong basis in mathematical logic. I was learning about…
Alex Jones
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Why do two reverse diodes represent the logic gate AND?

Consider: I can make no sense in my head how this can work. How is it possible to have a current flow through normal diodes from cathode to anode and represent an AND if both are 1?
user165500
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Why aren't many classical logic gates reversible?

It's mentioned in a textbook for quantum information that many classical logic gates such as the NAND gate are inherently irreversible. I'm confused why this is true. What does it mean by reversible? Why isn't NAND reversible?
Claire
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Is it possible to get this truth table working using only 2 gates?

Is it possible to get the following truth table to work using only 2 logic gates? W and CHS are inputs, and S and R are outputs. W CHS S R 0 0 0 0 0 1 0 0 1 0 1 0 1 1 0 1 Basically, I'm trying to control an SR flip-flop. With CHS,…
texel
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Are old logic gate components still profitable and widely used in industry?

I've noticed that many retailers still sell 74HC logic gate chips, which I also used in my digital design class. I'm curious to know whether these older components are still profitable for chip makers and whether they are still widely used in…
hskim
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Are there integrated logic gates "AND with one inverted input"?

I'm looking for an integrated AND gate with one inverted input that fulfills \$Y={\overline{A} \cdot B}\$ I know that I could invert one input with a common emitter configuration, however I prefer to implement this gate with as little passives and…
try-catch-finally
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Two reset sources for the CD4017 are interefering

I have a CD4017 counter configured so that any of its outputs can be connected to the reset pin. I also have a manual reset button connected to the reset pin, and this switch is buffered by a Schmitt trigger. The problem is that the Schmitt trigger…
Jay
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Help in the closing of a logic circuit

I'm currently studying logic circuits for my exams and came across a question "7. An electrical circuit is set up with four switches. A lamp will light only if the following happens: Switches A and B are both on. Either Switch C or Switch D is on,…
user63671
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"Double-pumped" flip-flop?

As of this moment, does anybody make a single-chip flip-flop that latches its state on BOTH the falling AND rising edges of a clock? In other words, instead of latching an input's state and setting its output's state to match ONLY when a clock…
Bitbang3r
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How could I essentially design an if/else statement as a circuit using basic logic gates?

So for my circuit, I have set up a simple game of rock paper scissors. I have the actual gameplay of rock paper scissors working, where it will correctly choose the winner and light up corresponding leds on an icestick. The way the game works is…
Withdrawnbean
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Logic Circuit - Integrated circuit to omit one pulse over two

I am trying to make a simple circuit to control two MOSFETs with only one PWM generator. I would like to send the red waveform to the PWM generator and I would like that after a simple circuit the MOSFET A and the MOSFET B receive respectively the…
Jess
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How does this "CD4069 smooth bargraph" work?

I saw this schematic and I had problems finding out how it works: As the voltage increases from zero, the first LED grows in brightness. Just when that LED is fully lit, the next LED begins to glow slightly. Each LED represents about 1 volt of…
Tirdad Sadri Nejad
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What if I close S3?

So I understand that if S3 is opened, then IC2A will receive in 1 VCC(high logic level) But if I close it will it be low level from ground (0) ? And if yes why? Why does VCC doesn't 'matter' anymore?
Elena
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Error in Practical Electronics for Inventors?

I’ve been studying this book for digital electronics. I think that the highlighted values in the operation of the shown AOI gate are not correct and should be 0 instead.
Atom
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I keep coming across the term "bubble pushing in logic gates."

Can anyone please simply explain to me what it is? A simple little lesson or answer would be appreciated.
Harminder johal
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