Questions tagged [multiplexer]
A multiplexer selects one of two (or more) inputs based on a control input. It then outputs the selected input.
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2:1 multiplexer in verilog on an fpga
I'm new to verilog.
I'm trying to implement a 2:1 multiplexer on a FPGA development board (DE1-SOC altera) using built in switches and LEDs.
The following are the assignments that I'm using for ...
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Why do 2-1 muxes forming 4-1 mux have common selector?
Why is s0 common for both 2-1 multiplexers? Shouldn't each one have it's own data selector? Doesn't such setup remove some of possible logical outputs from multiplexers, if s0 value is same for both? ...
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In a multiplexer, can you direct the input into all the outputs at the same time?
I need to direct a single line into multiple outputs, so I'm using a MUX to direct the input into the desired outputs (one at a time). However if i ever wanted to do a broadcast to all my output lines ...
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Multiplexer CD4051B gives strange readings
I'm trying to multiplex an analog input port on an Arduino Uno.
Datasheet
simulate this circuit – Schematic created using CircuitLab
I've connected the input to 5V for testing stability of ...
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How do I get my 555's output to cycle through different paths with just one button?
I'm an amateur so this is a basic question.
I have a 555 in astable mode producing a frequency which I put through a speaker as a musical note ("musical" is debatable). I can get lots of different ...
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Pic32MZ - ADC/Multiplexing?
Using PIC32MZ2048EFH144 MCU.
Datasheet: http://ww1.microchip.com/downloads/en/DeviceDoc/60001320D.pdf
12 Bit ADC
The board has 8 DMA Channels(Programmable/Dedicated). I am interfacing 10 ...
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How do you find out if a MUX is bidirectional
I've used this MC74VHC157 in a project thinking this would be bidirectional but I'm not sure. How do you find out if any MUX is bidirectional?
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How can 16 buttons be connected with only 8 wires?
Here is the product. I understand the idea: these 16 buttons use a 4x4 matrix. 4 lines for rows, 4 lines for columns, and we have 8 cables.
But:
How can this work without any multiplexer ?
Can this ...
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What is quad 8:1 MUX?
In my assignment i'm asked to show a block diagram for quad 8:1 Multiplexer. But i have no idea what the word quad means in this question. Can someone help me?
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Can I use a multiplexer to connect a small capacitor to a 555 timer?
I'm making a circuit including a 555 timer controlled by an RC combination, where R is fixed and C is one of several capacitors (values around a few pF to a few hundred pF). I would like to connect ...
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Full adder using 4:1 mux
I know how to create a full adder using a 4:1 mux with A and B as the select lines. However, now I need to create a full adder using B and Cin as the select lines.
the CoutMux and SumMux columns ...
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Decoupling capacitors for Multiplexer?
I am using a Board with a Cortex M0 to sample signals from force sensors. The sensors have a resistance that corresponds to the force applied, so I am using voltage dividers and read the voltage with ...
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How to build a 3-bit comparator using a multiplexer?
I need to (in design) create a 3-bit comparator using an 8-bit multiplexer and/or up to four 4-bit multiplexers. There are plenty of examples of how comparators and multiplexers works on the web. ...
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Number of not gates in multiplexer
I'm reading a page on multiplexers that has the following image. I says for constructing one it used 7 not gate. But looking at the image I don't know why three of them are needed. Could't you just ...
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FPGA basics and implementation help [closed]
I want to use an FPGA for my project and I want to use an FPGA as I want to implement the functionality of multiplexers within it.
Also I want to implement a microcontroller function within an FPGA. ...
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Audio Switching Circuit - Ground Loop Noise Problem
I'm building an adapter to connect an RJ9 headset output to a 3.5mm jack output(TRRS, mic included). I have designed it so far to use DG409 (4:1) analog multiplexers to choose what lines are connected ...
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Two multiplexed 7-segment displays flickering
I'm working on a temperature sensor.
I've got:
LM35 (Sensor)
LM741 (Op-amp to amplify LM35 Vout to 5V)
PIC 14F458
The temperature is shown on two 7-segment displays with only one BCD converter (...
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Multiplexing 2-Seven Segment Displays using ARM 7
I am currently trying to control two seven segment displays from the same 7 pins (P0.0 - P0.6) of an ARM 7 micro-controller. I am first testing this on Proteus simulation software.
I am following ...
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Clock multiplexor fanout buffer
I'm trying to find out if there is a clock fanout buffer with two-input multiplexing that allows each output to select the the input independently.
I found an IDT part that is a two-input ...
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MUX input debouncing?
I am using a CP2103 to interface with a simple 74HC4051 MUX. I want to use 3 of the I/O ports on the CP2103 to control the input pins of the MUX. The 4th I/O port is being used for something else. The ...
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Demux from 1 camera to 3 DVR's
Recently I have been experimenting on DVR devices. I have one camera however I want to demultiplex it to three 16ch DVR devices.
I have been able to create a daisy chain to connect all 16 channels of ...
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200 LEDs through Arduino via SN74HC595N shift register
From what I have researched, I can add more inputs/outputs to an Arduino via a shift register. I bought 10 SN74HC595N shift registers that have 10 outputs each (I think). I need to control two main ...
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Level shifting at the output of a 2:1 multiplexer
In my design a custom implementation of an Arduino Uno talks to either a CP2104 USB-UART or a bluetooth module, through a multiplexer (74LVC1G3157). Priority is given to the wired connection and hence ...
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7 segment LED display multiplexing for 9 digits
I want to build a 9-digit 7 segment LED display with basic components.
I am planning to use a 4-inch 7 segment LED display and an Arduino board for my application.
According to my understanding, I ...
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ADCs for sensor arrays
Most of the ADCs I see are designed for a single sensor voltage.
I have read that this is not a problem for something like an acoustic sensor like a hydrophone because the ADC can be multiplexed so ...
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Decoders and multiplexer connected [closed]
This is from an assignment. I don't understand how they came to the answer shown, can you please explain?
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What does this digital multiplexer (CD54HCT151) output when the selected input is floating?
I'm not sure if I missed something, or it's omitted from the datasheet, but in any case, I couldn't tell what happens on the output when the selected input is floating. This post seems to imply there ...
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Alternative-switching multiple busses
In practice, the effects/results described below are much easier to achieve with an MC -- I know.
However, for the sake of understanding and learning, I was considering the following scenario to be ...
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How to configure GPIO pins as digital outputs on LTC6804?
Can someone explain how to configure GPIOs as digital output pins on LTC6804. I have a MUX whose inputs are connected on GPIO2 - GPIO4 and the output is connected to GPIO1. My task is to control MUX ...
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Integrated Circuits for Signal Switching
Sometimes I need to switch digital signals between microcontrollers or devices. For example I have a serial device and I want to control to which microcontroller it is connected per digital pin. So ...
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Reducing the number of pins needed to read a 12-key keypad where the buttons are grounded?
Unfortunately, I'm not sure what the right question is; I'have a 12-key keypad. I wanted to utilise a matrix based approach, except that they all seem to be connected in such a way, that they're ...
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Is 74LS139 a DeMUX? If yes then how can I give it input and select lines?
I am trying to learn DEMUX.
So, I have a 4 Channel DeMUX Diagram:
From this diagram we can clearly see that a DEMUX needs 2 Select Lines and 1 Input to give 4 output lines.
After that I have taken ...
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Constructing a 4-way multiplexer composed of 2-way multiplexers
I've constructed a schematic of a 2-way multiplexer, and also have made a 4-way one (and have a good idea of how to make 8, 16, etc. ones).
However, my 4-way isn't a composition of 2-way multiplexers,...
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select any 2 of multiple inputs
I am trying to input any two of six sensor outputs to a microcontroller that has only two compatible ports.
My first idea was to use two 74hc4051 8:1 MUX IC's but it would require 3+3=6 selection ...
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Using analog switches with ultrasonic sensors, what to look for?
I am designing an anemometer for university project. I intend to use analog switches to switch between ultrasonic sensors. I use this circuit as my first stage - it adds offset to the signal and has ...
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4 To 1 MUX - Figuring out the inputs
If i have a 2to1 mux together with logic gates like this:
I can simply create a karnaugh map and test the different values of XYZ and get a function.
From this i get the function f = x'z + yz + x'y
...
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Over voltage and reverse voltage protection of multiplexed ADC with voltage follower
I am designing a protection circuit for the ADC section of a design I am working on.
There will be 8 analog signals being read by a single pin of the MCU via an 8 channel multiplexer. The analog ...
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How to calculate the segment array resistors in a multiplexed display array?
The situation:
Four seven segment displays are multiplexed by a 16F648A. Now I need to calculate the required value for the segment resistors.
Supply voltage 5V.
Datasheet:
Segment voltage 1,8V.
...
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Inside a multiplexer, can it work if i use a Pmos instaed of Nmos to reduce number of inverter?
To works well, inside a multiplexer we need the input signals inverted, but can we use a pmos instaed of a nmos with a inverted signal to delete the inverter?
Is there any thouble? PSpice give me some ...
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74HC4051 Alternative - 4 Channel 1 circuit?
I have been playing with this multiplexor recently: 74HC4051.
I have been searching all day for an alternative version where it is 4 channels instead.
My task is simple and perhaps I am using the ...
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Should I use a Dual 4-channel analog multiplexer/demultiplexer for powering up 4 sensors and getting their readings?
74LV4052
Dual 4-channel analog multiplexer/demultiplexer
I currently am using a multiplexor to connected to one analog channel from my Arduino. The multiplexor is connected to 4 pressure sensors that ...
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What is the purpose of diodes in flip-dot displays?
In most flip-dot displays i've seen, the electromagnets have a set of two diodes connected to them. This is also mentioned by David, who asked a question about the displays before.
However, in the ...
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Is it possible to use only ONE 4-to-1 Mux to allow 8 inputs?
So I am doing some CSE homework where we are told to implement a 3 bit equation using 8-to-1 mux and 4-to-1 muxs only which I understand. What I am wondering however is instead of cascading the muxs ...
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How does shift register works as I/O multiplexer
I was checking on eBay for a CNC controller. I came across this unit, which provides 64 buttons. The micro is a 28pin PIC chip but there are 8x LS165A IC's on it. I am guessing there is some sort of ...
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4 to 1 multi-bit multiplexer implementation [Q]
We are tasked with creating a 4 to 1 multiplexer with 4-bit inputs. I believe I fully understand how to create a 4 to 1 1-bit multiplexer, but I completely do not understand what the 'input' side and '...
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multiplexing several channels
I'm designing a 6-channel amplifier which requires one LPF, one HPF, and one gain stage for each channel. I use 4*1 multiplexers for LPF and HPF, and 8*1 multiplexer for gain to control these ...
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Simplify Boolean Equation to MUX
I have this Boolean equation which my professor told me it is possible to simplify to a MUX 4X1 but I can't do it. Would love some help!
\$f(A, B, C, D) = A'B'C'D' + AB'CD' + A'BC'D' + ABCD\$
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ATMega input buffer
What happens if a AVR ATMega controller is doing something else when a input arrives on one of the serial ports? Does it has some sort of input buffering?
I was thinking of using ATMega328 or simalar ...
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How would one construct a NxN crossbar switch from solid state components? [duplicate]
I was trying to construct a 10x10 cross bar switch using relays -- something like:
Question: is it possible to construct this by using solid state components (power transistors?) -- and if it is how ...
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What is this multiplexer doing in this design?
The design is from a Xilinx FPGA doc. I think these are preprogrammed look up tables because there is no select bit input, but on the bottom it says they are:
Multiplexer[s] Controlled by ...
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