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

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30 views

Mealy machine to detect sequence of 2 inputs

I have the following assignment for a project at college and I have a few questions regarding it. You are to design a Mealy state diagram for a digital lock. Assume that two debounced push-buttons, A ...
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0answers
41 views

pin connection added

I am trying to communicate 24 hall sensor via arduino & 8:1 Mux . I am using CD74HCt4051E 8:1 multiplexer. Instead of hall sensor i have used potentiometer 24 nos and connected to MUX IC devide ...
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0answers
71 views

4x4x4 LED cube using 74hc595 shift registers

I am currently planning on building a 4x4x4 LED cube. It will be organised as 4 layers of 4x4 matrices where the cathode of each 16 LEDs are soldered together. The anode of each of the 16 LEDs are ...
0
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3answers
91 views

Audio Signal Switching - “DPDT switch vs. 4066”

I've got a signal coming from an electric guitar and I need to switch it. Basically it's a distortion circuit. I need to switch between the distortion and clean (directly connected to the output) My ...
0
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1answer
54 views

PIN selecting problem over arduino

My schematic as below. I have connected 8 hall sensor as shown in picture. Problem i am facing here is SO, s1, s2 The Led light are not glowing .Even the forard voltage across is 3.9v. i have tested ...
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1answer
46 views

Implementing F using a demultiplexer and an extra AND gate

Use a 1-to-8 Demultiplexer and an extra AND gate to create the function: F(x,y,z) = ∑m(1,3,5) If I were using an OR gate I think this would be trivial, simply put the 1 3 and 5 ...
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1answer
54 views

Multiplexer CD4067 bug:signal appears in unselected channels

I connected a multiplexer CD4067 with arduino. I will select ch0-ch15 in turn and pass the selected channel to A0 on arduino to do AD Convert. Then I only connected ch0 to 5V on arduino and selected ...
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0answers
46 views

High-voltage seven segment LED display driver problem

I've a circuit similar to THIS project, with a 74LS04 as inverters instead of 74HC54 (tested 74HC04 and CD40106 too) and ULN2003 instead of ULN2803. The circuit seems to work perfectly but when I turn ...
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2answers
64 views

Multiplexing problem with Arduino, MAX7219 e BJT

I tested the circuit below with an Arduino UNO, a MAX7219 and BC338. The sketch in Arduino is a chaser, so the leds should turn on in sequence. It consist of 7 segment (A-G) and two Digit (0-1). The ...
2
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1answer
58 views

A circuit that outputs one input voltage by default, or another if it is present

I'm trying to come up with a simple design that will take two analog inputs voltages (~0.2-1.6 V each). One is an "internal" voltage and should always be present. The second "external" input can be ...
0
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1answer
53 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 ...
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2answers
88 views

How does one implement the following function with these tools provided?

Suppose I have a function defined as follows, such that it is expressed in POS form, with the product of the following max terms of 4 variables (A,B,C,D): 0,3,4,7,9,10,12,15 and I only have a 4 to 1 ...
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1answer
37 views

Can avrdude address individual usbtiny programmers?

I'm envisioning a panel programming jig. In my mind, it consists of a Raspberry Pi, a powered USB hub, and a collection of usbtiny clones each connected to a pogo jig and a target on a panel. The ...
0
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1answer
179 views

Custom built 16x32 (40) LED Matrix controlled by Arduino

I am planning to build a clock / thermometer / info display. I have ordered 10 pieces of 8x8 LED matrixes from ebay (http://www.ebay.co.uk/itm/331064583297). As this is not a pre-built one I have got ...
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0answers
21 views

MAR /MBR / MUX Device

How can I modify this circuit to permit loading of the MBR from either the hex keyboard or from memory. As it is, the circuit can only load the MBR from user input.
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1answer
60 views

3 State Shift Register with 2-to-1 multiplexers

For a homework assignment I need to Redesign the right-shift register circuit of Figure 12-10 using four D flip-flops with clock enable, four 2-to-1 MUXes, and a single OR gate. The figure ...
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1answer
68 views

Strategy for up to 40 ADC inputs using alert feature

I'm working on a project where I want to monitor 40 phototransistors (IR breaker beams), but without having to constantly poll the ADCs. Ideally I'd want a digital pin pulled when one of the beams is ...
2
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2answers
114 views

Is it possible to drive a 4x4 RGB common-cathode LED matrix with a MAX7219?

The MAX7219 (datasheet) is a LED matrix driver that's designed to drive an 8X8 single-colour LED array. tronixstuff has an intro on how to use it with an arduino that has some relevant diagrams. I'm ...
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1answer
67 views

Transistor Isn't Forming the Connection

I have wired the following diagram. simulate this circuit – Schematic created using CircuitLab My understanding of transistors is relatively poor, and thus I am assuming it has to do ...
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1answer
95 views

How to increase current output of a multiplexer for activating a relay

I want to make a multiplexer for my project which needs 24v dc to operate. I am using an OR Gate IC for generating an output. My 4 gate inputs are connected to 6V battery power and I am getting a 6V ...
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2answers
104 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
46 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
77 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
152 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
845 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 ...
2
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2answers
186 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
162 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
83 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
92 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 ...
0
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2answers
68 views

Multiplexer CD74HC4051, connections and parameters

I'm testing a multiplexer from Texas Instruments, below is shown the cabling I've done. But varying the select pins(9,10,11) has no effect, nothing happens. The LED always stays on. Vcc is 5v ...
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1answer
179 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
40 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
71 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
88 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
74 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
57 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
155 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. ...
0
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1answer
226 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 ...
0
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1answer
136 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 ...
0
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3answers
185 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
286 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 ...
0
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1answer
84 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
66 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" ...
0
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1answer
78 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 ...
0
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1answer
95 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
votes
1answer
70 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. ...
3
votes
2answers
177 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 ...
6
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1answer
244 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
162 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
233 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 ...