Electrical Engineering Stack Exchange
Electrical Engineering Stack Exchange

Questions tagged [multiplexer]

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

Multiplexers switch between 2 or more input channels to one output channel. Each input channel can consist of one or more bits. For 2 input channels 1 select bit is needed, for 4 input channels 2 select bits, and for 8 input channels 3 select bits.

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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 as a slave. How would I increase the number of…
Manishearth
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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 to suggestions if anyone thinks a different…
littlebirdceo
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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 knowledgeable explain any other trade-offs?
Chris B. Behrens
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Reading a huge number of analog sensors in real time

I'm trying to build a MIDI-like controller that has a neck like a guitar. On that neck, there is a huge matrix of pressure sensors. The controller will emulate 3 strings. The way this works is: There are 3 long strips of double sided copper tape…
d.oelert
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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 Arduinos? I would like to be able to…
kaffolder
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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.
tollin jose
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LED Multiplex Anode-Row Driver

I'm helping build this art installation that amounts to a large 16 x 16 pixel display. I settled on using 16 TI TLC5926 constant current driver chips chained together to give me direct drive to each LED. In retrospect I'm doubting myself and…
vicatcu
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Difference between Multiplexer/Demultiplexer and Analog Switch

What (if any) difference is there between mux/demux IC's and analog switch IC's? I'm comparing this in the context of chips with the same IO lines (for example a 1:2 or 2:1 mux/demux vs. a SPDT analog switch).
helloworld922
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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 I'm looking at the wrong places but somehow I…
Saad
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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 LEDs at a time. Am I limited to only 6 LEDs…
JYelton
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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 detect accurately presses of multiple buttons?…
Basj
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Miniature Traffic Light with Raspberry Pi: Wiring many LEDs

Background: I am a Civil Engineer specialized in traffic control devices and I have a small hobby project to build a scale model traffic light system. I can manage and control the traffic light pattern programming on my own using a Raspberry Pi…
SkyNT
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Serial control of 25 LEDs from a single pin

I have a microcontroller with one available digital pin. How can I control 25 LEDs?
archgoon
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Use of tristates vs multiplexers in a RAM

Why are tristates favored over multiplexers to select the output from RAM? The explanation that I've heard of is that the RAM is too large for using a multiplexer but I need more details. A theory we've come up with is that using a multiplexer would…
Sid
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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: $$ F(A, B, C, D, E) = \sum ( 6, 7, 12, 13, 14, 15,…
user1969903
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