Questions tagged [logic-gates]
Symbolic representation of ideal devices implementing boolean functions
1,437 questions
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SAR ADC 4 bits working in static but not in dynamic
I'm currently working on a project involving building a 4 bit SAR ADC converter using a voltage ref of 5V:
Actually I've got that artchitecture:
One-Hot Ring Counter (Sequencer) (HB 7) build from D ...
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LTspice Simulation not matching theory (CMOS implementation of a NOR gate)
I've just began learning how to use LTspice and I started by trying a basic CMOS network for a NOR gate .
However, when I run the simulation i've got my "logic 0" as 3.72...V instead of flat ...
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AND gate logic working as conditional power
I am trying to make a circuit that gives power only when all the conditions are true. I am planning on using bjt to do the job. Here are two ltspice simulations i have run. Assume the load to be ...
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How to make a logic circuit with LEDs as opposed to 1N4004s or the like?
Basically the title. I want to build a simple diode-resistor AND gate. I set one up in a simulator (I used both Falstad and TinkerCad)
simulate this circuit – Schematic created using CircuitLab
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Propagation delay in a ripple carry adder depends on the bit pattern
Please help me understand how propagation delay changes depending upon the input bit pattern in a ripple-carry adder.
Take 2 cases:
100+011. here no carry generated or propagated
001+111. here carry ...
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Threshold levels doubt on logic gates datasheet. Limit and typical values meaning
I'm working with 74HCT1G32 but I'm not sure how to interpret the datasheet value for high and low level voltage.
Let's talk, for example, about the high level.
In datasheets from other manufacturers, ...
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How to make two components trigger together?
I have a feedback circuit for a device I am designing. The goal is to sense temperature changes with thermistors and then if certain conditions are met I want to use an analog switch to disconnect a ...
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Is 74LS00 max current a capability or a limit?
a newbie question here.
Many datasheets specify the max input/output current for the integrated circuits. I'd like to know if that is the maximum they can provide or the maximum above which they break....
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Controlling 7-Segment Display
I am redesigning the control panel for a project I have been working on. I am using a rotary encoder to replace a set of 3 rotary dials, but I cannot use any microcontrollers or programming.
I plan on ...
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Will this work as an XOR gate?
Will this work? This will be part of a bigger circuit. But I first need to know if this circuit will work as an XOR gate.
The transistors are 2N2222 NPN transistors and the led is a typical red led ...
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Why does my Logisim FSM assert incorrect outputs for given input codes?
I’m designing a 3‑state finite state machine (FSM) in Logisim, with all inputs, outputs and states encoded, but when I apply certain input combinations the outputs don’t activate as I expect. Below is ...
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Logic Problem: "Selective AND Gate?"
I need a logic element with two inputs: A (the output from a zero crossing detector) and B (the output from a voltage comparator), and one output: Q (enabling a gate driver).
When both A and B go high,...
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How to find the signal that has the first rising edge
I'm working on creating a logic circuit that can detect which of the signals B and C have the first rising edge after a falling edge of signal A. The output should be low if B is first and high if C ...
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Minimizing a logic circuit using custom weights for the logic gates
Question
There exists tons of software that can minimize a logic circuit by providing a solution using the least amount of logic gates.
What I am interested in, however, is not the total number of ...
