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

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83 views

Shift registers(?) failing after being left on a while

Resolved: SLCLR on SN74HC595 was not tied to VCC, so behavior was inconsistent. I have a custom built board that is running seven 7-segment displays, multiplexed using SPI from an 5v Arduino Pro ...
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2answers
36 views

How are the Intersymbol Interference and Symbol Time (duration) related to each other?

In a lecture slide I noticed that OFDM(Orthogonal frequency-division multiplexing) mitigates the problem of Intersymbol Intereference over wireless systems because the symbol time is increased, in ...
0
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1answer
64 views

Circuit design for short-circuting outputs when needed

I am working with two sensors with 4 pin as output. My question is simple: I want to make circuit that allows me to short circuit the output of either one of the sensors individually when needed. ...
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3answers
130 views

Driving 60 signals one at a time, in constant sequence

I have an application where I need to turn on/off one of 60 signals one after another in a constant order, ever repeating. (1, 2, 3, ... 59, 60, 1, 2, ...) Only one signal is on at any given time. The ...
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6answers
810 views

What's the maximum number of outputs you can control from a microcontroller with n outputs?

Been pondering this for a while, and I think it's \$2^{(n-1)}\$ outputs. If I have 5 outputs, I'll use 1 as the signal, and the other 4 as control lines to cascaded decoders, which gets me 16 ...
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2answers
67 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 ...
2
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0answers
116 views

What's up with my 74HC4052?

I am using a TI 74HC4052E to multiplex a TTL UART on a Microchip PIC32MX695F512 microcontroller. The expected behavior is for the TX and RX signals to pass through the switches unaffected; sadly ...
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0answers
36 views

8 IR sensors and 74HC4051 multiplexer where to place low pass RC filter?

So I've got 8 IR sensors like these Then I connect them to multiplexer. And arduino will run mux's selectors through the loop.. Something about 5-10 times per second(read every sensor 5-10 times ...
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1answer
65 views

Multiplexer CD74HC4051, always giving a true out

I'm testing a multiplexer from Texas Instruments (CD74HC4051). Both +5V and Ground rails are connected to the Arduino Duemilanove board. I've got a +5V signal in the channel A7 (pin4) and A0 (pin ...
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2answers
41 views

Multiplexer CD74HC4051, connections and parameters

I'm testing a multiplexer from texas Intsruments, this is the cabling I've done, but varing the selecting pins(9,10,11) nothing happens. The led always stays on. vcc is 5v connected to arduino board. ...
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1answer
75 views

Arduino HC-SR04 sensor through CD74HC4051E multiplexer using single wire

I'm trying to get distance using HC-SR04 sensor and arduino. I've connected together Trig and Echo pins on the sensor, then it goes to port A7(pin 4) of multiplexer(selectors configured as follows: S0 ...
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0answers
37 views

Multiplex error

I am trying to do basic multiplexing to see if I can get the basics down. When I apply my pins 7,6,5,4 the LED's go on, but if I remove the pins wires the LED's go off. I make sure to apply no power ...
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2answers
66 views

Need an extra pin to control my driver board

I've been searching for a way to add an extra pin to a driver board. The MCU board that i'm using only has 8 pins on the left side and i'm already using all of them. 2 are for powering the driver and ...
1
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3answers
51 views

Dimension RGB LED for peak current

I would like to drive a 3x3 RGB LED matrix multiplexed. This means each RGB LED has 1/9 duty cycle and that means it consumes 1/9 of total current. The RGB LED I am using is designed for max 35 mA ...
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2answers
65 views

Mulitplexer to read analog values

simulate this circuit – Schematic created using CircuitLab I have a hall sensor that can measure current up to 25 A with analog output 0~5V. I am using Arduino mega board for programming. ...
0
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3answers
43 views

Understanding Digital Multiplexing

As I understand it, digital multiplexers contain multiple inputs (2^N), one output, and N selector lines. The selector lines are used to select which input is mapped to the output line. I then ...
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2answers
85 views

Multiplexing signals of two wires of a BNC cable and transmitting over a single wire

Background: I have a normal CCTV camera (650 TVL) . It requires a BNC cable in order to feed video signal from camera to DVR. Problem The problem is I have only a single copper wire from CCTV to DVR. ...
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1answer
129 views

XY table using motorized potentiometers

I'm trying to implement a XY table using 4 units of these motorized potentiometer, controlled by an Arduino. Since I have other uses in mind, I'd like to use as few pins as possible, wich would imply ...
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1answer
85 views

Multiplexing 4 DC motors with arduino

I'm aiming to control 4 motorized faders with an Arduino. However, I'm still trying to figure out how to best multiplex all the inputs/outputs. Each fader has two potentionmeters and one touch ...
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3answers
86 views

Can I get away with multiplexing an array mechanical Relays via Mosfets?

I want to use an Ardiuno to drive a Matrix of TO-220 Mosfets triggering mechanical relays instead of LEDS. I am making an array of glow-tubes (read: flickery, purple lightbulbs) as a dramatic screen ...
2
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0answers
109 views

Driving multiple stepper motors

During the last days I've been working on driving multiple stepper motors (28BYJ-48 – 5V) with SparkCore and Stepper.h arduino library. I'm trying to drive some stepper motors, but without having to ...
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1answer
59 views

{Multiplexors} combine 2:1 to from 8:1

I have a question of combining 2:1 to form single 8:1 multiplexor This is acheivable by using 7 2:1, with 4 of it at the first level, 3 of it at the second level, and 1 of it at the third level. ...
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1answer
55 views

Regarding OFDM (Orthogonal Frequency Division multiplexing)

Could you please briefly explain the IEEE 802.11a OFDM packet structure? In particular, What is meant by "symbol" here? What is the purpose of the packet preamble? What is a "short training symbol" ...
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1answer
61 views

What is the distortion introduced by a multiplexer?

Question in short: If I have a multiplexer, and my selected input is X volts, I suppose that the multiplexer's output will be X+-ΔX volts. How can I calculate ΔX ? Question with more details: I ...
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1answer
58 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 ...
2
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1answer
58 views

What would the firmware to control Shift1 system (for 1-pin shift register operation) look like?

This is a follow on question from this answer by Spehro Pefhany, in which he explains to us how to use 74HC595 serial shift registers with only one digital output pin. Below's the picture he posted. ...
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2answers
152 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 ...
5
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1answer
208 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.
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2answers
136 views

Select channel from multiplexer to show temperature values in c programming

I have question regarding selecting channel from multiplexer. I'm trying to receive some temperature reading from the two sensors which shared the same address and while I'm using one sensor, it can ...
3
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1answer
199 views

How do “beyond the rails” analog switches work?

I'm familiar with using CMOS switches ("transmission gates") for switching analog signals, but you can't use them for switching voltages beyond their supply rails. (So if you have a single supply ...
3
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2answers
134 views

How can I multiplex my oscilloscope probes?

Let's say that I'm tasked with the job of measuring the propagation delay of each inverter in a 7404 hex inverter. I've got a pulse generator, a power supply, and an oscilloscope with two probes, so ...
2
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4answers
197 views

250 LED control

I am in the process of designing an automated rock climbing wall that will have 250 monocolor LEDs lit in a predetermined pattern that will be changing every 10 seconds. My controller (actually a PLC) ...
0
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1answer
58 views

Multiplexing and electric capacitance

I'm working on a project, it's basically a hand-drawn paper keyboard based on capacitance. I was thinking I can multiplex the different lines with shift register (74HC595) and switch (4066), and as ...
0
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1answer
170 views

How does a HCF4051BE multiplexer work, at a very simple level?

I'm a totally noob, so please, take this in consideration when replying :) I want to understand how this multiplexer works. I tried to Google it, but all the answers was too advanced for me. I mean, ...
3
votes
1answer
457 views

Capacitive touch sensor grid to the Arduino?

I am trying to build 8x8 grid that consists of capacitive sensors which we have successfully made by using a high resistors and copper sheets. I used Arduino's library to control it, but my problem is ...
1
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1answer
112 views

Switching 100 different LM35 with one uC [closed]

I want to read the temperature of about 100 different LM35 with only one ATmega16 or ATmega32. I want to read 8 LM35 at one time and switch to the next 8 and so on. what kind of multiplexer or switch ...
0
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1answer
132 views

MCP23017 in series

I have a hand full of MCP23017 (16 bit multiplexers/ I/O Expander) but I can only get 8 IC on the bus due to the limit of address but I need 200 pins (about 13 ICs) for a 8*8*8 RGB cube and was ...
5
votes
2answers
162 views

Slow PNP turn-off time, how to optimize it

I'm multiplexing a pair of Nixie tubes. The high-side control is done with two pairs of transistors, MPSA92 high-voltage PNP to switch the 160V to the tubes, and a BS108 to control the base of the ...
0
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2answers
148 views

Is it possible to monitor analog multiplexer inputs without changing the selector signal?

If you have 8 analog input sensors (or 2 or 9 or 738479) is there a chip / is it possible with microprocessor programming to actively monitor all of the channels? Say you had 8 rotary potentiometers ...
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0answers
36 views

Is my interpretation of this problem regarding a 7-word mux correct?

I have a problem on an assignment which states to draw a block diagram for a 7-word MUX and determine how many control switches it should have. I'm not exactly sure what the problem means by "7-Word." ...
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0answers
227 views

Counters VHDL multiplexer 7 segment

I am new to vhdl and my code may seem stupid but i am still struggling i am trying to make a bcd counter using spartan 3 kit i have a problem multiplexing the 7 segment and i know i should use ...
0
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4answers
146 views

In CMOS, can I assume the delay of a multiplexer is negligible compared to the delay of an inverter?

Let say I have a ring oscillator, and I modify the ring so that the output of an inverter is connected to an input of a 2-to-1 MUX, and the output of the MUX is connected to the input of the next ...
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0answers
180 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 ...
1
vote
4answers
90 views

Multiplexing RF Sources to a Single Output

I have two wide-band VCOs, one 800-1600 MHz and the other 1600-2700 MHz which I would like to multiplex so that they can share the same output (SMA jack). (They are both configured to produce ~5 dBm ...
0
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0answers
56 views

Making a 2-bit 8x1 source selector from 2 1-bit 8x1 Multiplexer

I am working on a prelab for my Digital Logic Design course and this is the question I have been given. I have to use WinLogiLab DigitalSim utility at first to create this, but due to limitations must ...
2
votes
2answers
181 views

ATtiny/ATmega programmer board - need a 6 x 1:3 Mux solution

Hey so I'm trying to create a circuit on perf board that allows me to program three different types of chips using an Arduino Duemilanove as ISP. Those chips are the ATtiny85, ATtiny84, and ...
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1answer
321 views

Is there an easy way to multiplex the state of multiple switches in an AC circuit?

If I had a circuit like this... *Blurple boxes represent unknown devices/circuitry What would be the simplest way to transmit the states of the switches, using only a single wire? In essence I'm ...
2
votes
1answer
54 views

Multiplexing a phase shift keyed signal

There are a number of great tutorials online explaining phase shift keying as a means of digital wireless communication, but none of them seem to cover the topic of multiplexing. At first glance, it ...
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1answer
110 views

implementing palindrome using 2:1 multiplexer

A 4 bit number , ABCD is a palindrome when A is equal to D and B is equal to C . Draw a circuit to check whether a given 4 bit number is a palindrome or not. Use only 2:1 multiplexers.Do not use any ...
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1answer
62 views

What is maximum frequency of ADG506 Multiplexer?

I want to use AD506 as a multiplexer in a high frequency design (50MHz). It receives 1.2 Vpp sine wave signal from AD9850 and sends the signal for amplification. According to page 2 of its ...