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Questions tagged [multiplexer]

A multiplexer selects one of two (or more) inputs based on a control input. It then outputs the selected input.

11
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1answer
810 views

Why two inverters cascaded in multiplexer control signal terminals?

Why cascaded inverters are used in the multiplexer when it is possible to realize the circuit using a single inverter.
6
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7answers
11k views

Multiplexing Inputs on a microcontroller

I have a 4 way DIL switch that I use to provide input to a microcontroller, and I need to free up a port to use for something else. Is there a way to multiplex 4 inputs into 3 microcontroller ports? ...
6
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3answers
9k views

Best way to control 130 - 140 LEDS with Arduino Uno 32/64 bit led drivers?

I am new to electronic prototyping and had a few questions. I need to control 132 LEDs individually. I want to make 3 rows ( 2 rows of 60 and 1 row of 12) I think i can matrix them but i would still ...
5
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5answers
9k views

Multiplexing two 7-Segment displays (Ghosting issues)

I am currently working on a simple scoreboard using two 7 segment displays, a shift register (74HC595N), two PNP transistors (2N3906) and an arduino uno. Each 7 segment display is common anode, ...
5
votes
1answer
569 views

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 ...
1
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1answer
3k views

Learning Multiplexing with LEDs, transistor switching speeds

I am working with some friends trying to multiplex. The issue we run into is we aren't sure if we are hitting a limit on transistor switching speeds. I am unsure if this is a hardware or software ...
26
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15answers
25k views

Controlling 500 LEDs with PWM

I'm considering taking on a project that would involve individually addressing 500 LEDs, optimally with PWM support for each. I'm planning on using an Arduino since I already have one, but I'm open ...
17
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2answers
6k views

Is Multiplexing ever superior to Charlieplexing?

I've reviewed the two methods, and multiplexing really only appears to have one advantage, that it would be easier to track down a failed LED than in a Charlieplex array. Can someone more ...
3
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3answers
578 views

How to short two nodes electronically

I am using a Phillips SAA3010 IR transmitter IC to send a modulated IR signal. The IC has two types of inputs: Z0---Z3 X0---X7 And one type of output: DR0---DR7 Each legal operation corresponds to ...
1
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1answer
29k views

Design a full adder of two 1-bit numbers using multiplexers 4/1

How can i implement the full adder of two 1-bit numbers using only multiplexers 4/1? I created a truth table for a one-bit full adder, which looks like this: A = first bit B = second bit Pu = bit ...
0
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2answers
4k views

barrel shifter using multiplexer: how to go about it

I am trying to under stand how to build a barrel shifter using multiplexers. I understand how the barrel shifter works but I don't get how you decide the number of multiplexers to use, and how the ...
0
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1answer
121 views

Multiplexer handling 16 bits

Design the VHDL components (Register, Decoder, and two Multiplexer 16 bit) and interconnect them to build a register file. The schematic shows only four registers. Your solution should implement ...
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1answer
1k views

Time Division Multiplexing question [closed]

I am new to the concept of Time Division Multiplexing in school, after reading a few books I came over this question. With the help of sketches explain Time Division Multiplexing (TDM) in terms of ...
25
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3answers
32k views

How do I extend the number of analog (input) pins available to me?

I already know how to extend the number of digital pins on an Arduino using a multiplexer. I want to increase the number of analog input channels that I have. One solution is to add another Arduino ...
10
votes
6answers
18k views

How can I control many LEDs with just a few pins on my micro?

I am using an Atmel ATtiny13 which has a 6-pin I/O. I'd like to control about 15 LEDs but am unsure how to connect everything. Without multiplexing of any sort, it seems I'd only be able to control 6 ...
5
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7answers
5k views

How can I control 128 (or more) solenoids?

I need to switch 128 solenoids either on or off individually, several times a second. I'd like to drive this from either a PC, or an embedded device. How would you recommend I do this? Perhaps ...
8
votes
3answers
34k views

How do you implement the following function using nothing but 2:1 MUX?

I am having difficulties understanding how to implement boolean functions, particularly given that I may only use 2:1 muxes and the variable D as a residual variable. The function is as follows: $$ ...
10
votes
7answers
30k views

How do I control several hundred individual leds with Arduino(s)?

I am working on an electronics project which involves hundreds of LEDs. (Talking upwards of six to seven hundred LEDs...a lot, I know.) Is there any way to control this many LEDs with one or a couple ...
10
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6answers
6k views

Large Multiplexers/Data Selectors

I'm looking for a multiplexer IC with 128:1 or more inputs (256 would be quite nice). I would have thought such a device would be quite common yet I'm having a tough time locating it. It could be that ...
8
votes
9answers
2k views

Serial control of 25 LEDs from a single pin

I have a microcontroller with one available digital pin. How can I control 25 LEDs?
3
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2answers
480 views

How to “deserialize” a digital output to 4 digital outputs

I am working on a small test project for my Arduino and as part of it, I want to display a number on a 7-segment LED system. My first setup involved just direct links to the 7-segment display and ...
1
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4answers
9k views

Is it possible to drive 4 seven segment display with MSP430G2231?

I'm trying to teach myself electronics and my goal is to create a digital clock with 4 digits. I have an MSP430G2231 which has only 8 available ports as far as I can tell. I saw some methods for ...
5
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2answers
2k views

32 bit, 4 way multiplexer

I'm relatively new to electronics and recently decided to design and build a very simple CPU as a personal project. My instruction size is 32 bits and I want to have 32 bit registers so I am going to ...
5
votes
2answers
2k views

Using the raspberry pi to measure multiple electrical circuits

I am looking to use the raspberry pi to measure the power consumption of multiple household electronics and record the information to analyze later on. However, I'm not sure if it's possible to ...
4
votes
1answer
9k views

How to create an n-bit multiplexer?

I'm needing to create a 4 bit, 16 input multiplexer. I know I could describe this as a long list of S => when "0000" etc.. but I think that's not very clean, and ...
2
votes
3answers
2k views

Best way to build a 64-bit output multiplexer

I'm looking to create something to multiplex N 64 bit signals together. The goal of the project is to provide digital switching between a library of old cartridge based video games. Essentially I ...
0
votes
1answer
2k views

i2C multiplexer to use multiple sensor of the same type

I would like to hook up multiple sensor of the same type (temperature, pressure and so on). The problem is that each sensor can only have 2 different unique values for the register, so can't put more ...
6
votes
4answers
2k views

Multiplexing a Circuit

Frankly, I'm overwhelmed with this circuit that I have to start building in lab tomorrow. Last week we built an octal decoder that takes a 3-bit binary input from 000 to 111 and displays a unique ...
6
votes
2answers
3k views

7-segment LED display with multiple digits

I was looking at the datasheet for the LTC-4627JR, and it looks like each digit shares a common anode, and each segment shares a common cathode. My question is given this configuration, I don't ...
2
votes
4answers
2k views

Multiplex dip switch input to microcontroller

I have 3 DIP switch packages with 8 switches each, and not enough inputs on my microcontroller. This article (you have to download the pdf to see the schematic) gives an example of what I want to do. ...
2
votes
3answers
4k views

Three Phase Input to Single Phase Output

We have three phase input and the voltages in the three input is not the same always. Sometimes, one or two or three phase will be off. I would like to connect the phase to output which lies within ...
2
votes
4answers
507 views

High voltage high bandwidth analog mux

Does anyone know some ref of high voltage high bandwidth analog multiplexer? I am looking for a mux that can tolerate input voltages up to 10V, but has also a high bandwidth of at least 1Ghz. I am not ...
2
votes
0answers
661 views

MCP4131 resistor on SDI/SDO multiplexed pin?

I'm using the MCP4131 digital potentiometer to control the brightness of a LED using an Arduino Uno. The MCP4131's interface is SPI and it has a multiplexed SDI/SDO pin (pin #3). The datasheet ...
2
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2answers
3k views

MUX verilog code

Can anyone explain the difference between the two codes below. Both written in Verilog, Xilinx. If someone can explain how the second one works would much appreciate it. ...
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0answers
377 views

Discrete logic multiplexer

I posted a more in-depth outline of what I'm doing here, but basically I'm building this circuit (for n=3): The circuit displays an output based on the combination of three three-input DIP switches. ...
1
vote
1answer
393 views

LED and Button Matrix multiplexing?

I have only six GPIO to control a piezo buzzer and 6 LEDs and read 6 buttons... Would multiplexing the 6 LEDs/buttons in a 2x3 matrix work like this (i.e. 5 pins for the 6 LEDs and buttons, one ...
1
vote
1answer
468 views

Reading 16 voltages accurately with three decimals on Arduino

I need to monitor 16 LiFePO4 cells. Their Voltage during operation measures from 3.0 to 3.7V which I would like to measure accurately with 3 decimals. I was thinking of using a 16 port multiplexer ...
1
vote
1answer
2k views

NPN or PNP for multiplex seven segment display?

I want to put three multiplexed seven segment displays on a pcb module which then will be connected to another board through a 1x12 Pin header housing an ATMega (so assume in the following that Pin 11 ...
1
vote
1answer
1k views

How much is the noise of a multiplexer for analog inputs?

I have 4 sensors, each have with two differential output (S- and S+) that I need to use in a differential amplifier (with a gain equals to 1000 in my case). The difference between S- and S+ is ...
1
vote
2answers
785 views

Boolean expression of MUXs

I want to make sure I understand writing boolean expressions for MUXs. For F0, I derived the following boolean expression: \$\ F0 = S1’S2’(A’B + AB’)\$ from this circuit: Is this correct? If so, is ...
1
vote
3answers
2k views

Why is the output (in the truth table) inverted in a ic 74154 used as a demux?

I am studying Digital Principles and Applications from Malvino and Leach. I have a doubt in the demultiplexer section. This is the image of a 1 to 16 demux. I understand how it works. So, if ABCD = ...
1
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0answers
97 views

prioritized power path controller for battery backup [duplicate]

I'm searching for a simple solution for a prioritized power path controller to maintain a system supply line through a rechargable battery when the main supply fails. My goal is to make the cheapest ...
1
vote
4answers
3k views

Difference between i2c switch and i2c mux

I am working on a project which involves reading from multiple IMU sensors on i2c protocol. They have a fixed i2c address and hence I feel the requirement of some sort of multiplexer. On some ...
0
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1answer
244 views

Mealy Safety Device with 2 inputs

I have an assignment in college and I would like to ask some questions: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are available ...
0
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2answers
901 views

Programmable gain instrumentation amplifier with R-2R ladder and analog multiplexer

I want to build a programmable gain instrumentation amplifier with power of two possible gains (1x, 2x, 4x, 8x...). Is there a way to use a R-2R resistor ladder and an analog multiplexer in order to ...
0
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1answer
3k views

How do I find the Truth Table for Mealy State Machine?

This is a followup to my previous question: I have this assignment in college: You are to design a Mealy state diagram for a safety device. Assume that two debounced push-buttons, A and B, are ...
0
votes
1answer
374 views

Maximum current on CD74HC4067

I want to build a smart locker using this part https://www.aliexpress.com/item/32845920160/32845920160.html and a CD74HC4067 multiplexer. Essentially I need to turn on only one lock at time using a ...
0
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2answers
492 views

Designing a good RF Transmission/Reception system for Embedded System

I want to have 4 sensors transmitting information to a microcontroller ie 4-bit Encoder -> Transmitter >>>>>>>>>>>> Receiver - > Decoder -> MCU The problem I have is that if I use 4 transmitters and ...
0
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2answers
434 views

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 ...
0
votes
3answers
714 views

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 ...