Questions tagged [charlieplexing]
Charlieplexing is a multiplexing technique allowing to control N \$\times\$ (N-1) LEDs or buttons with N I/Os.
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Bigger Matrix with the IS31FL3731
Normally the IS31FL3731 makes a 16x9 matrix using two Charlieplexed arrays. I want to make a bigger square array, around 12x12 say. Is it possible to wire connect the IS31FL3731 in such a way that the ...
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How can this MOSFET steer the current of this LED driver?
I am powering a Charlieplexed LED array with this current source as shown in the first picture attached:
One requirement was to be able to control the current so I decided to insert an array of ...
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Driving 8 Leds from 4 pins of microcontroller
Is it possible to drive 8 Leds with 4 pins of microcontroller according this picture? Only one Led has to light at the time. The rest two pins will be always high Z. I tried to simulate it, there is a ...
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Will these optocoupler configuration work to tri-state high voltage GPIOS?
I am trying to control an array of LEDs that require a very high voltage due to the high impedance of the connections (there is no option to change that).
Since the charlieplex configuration makes use ...
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How can I control a "high" voltage charlieplexed LED array?
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I want to design a system that allows me to control different LED arrays that I have, which can be either conventional multiplexed arrays (MP) or charlieplexed arrays (CP), by just plugging ...
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Control 16 motors with 8 relays
I build a project using 8 relays in a matrix (charlieplexing) to control 16 motors (actuators), plus one relay to control two DPDT relays to reverse the power for the motor to turn reverse. I only ...
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Trouble understanding Charlieplexing problem
I am trying to make a circuit that uses 3 pins to drive 6 LEDs using charlieplexing. The cicuit im using is this:
What I don't understand though, is that when I want to turn D1 on, PB0=1, PB1=0, and ...
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How can I use Charlieplexing with common anode RGB LEDs?
I've an ESP32-based dev board (LoLin32) which has 26 digital I/O pins. I want to connect 25 common anode RGB LEDs to it. Connecting them in the 'normal' way would require 75 I/O pins, which I don't ...
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Charlieplexing ledstrips together
I know there is a lot of charlieplexing tutorials out there but non of them are very suitable for my case. I want to charlieplex 4 ledstrips together and control them by an arduino. This means that i ...
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Reading an LDR array with a Raspberry Pi
I am trying to repurpose a replica GPO 746 using a Raspberry Pi, however the rotary mechanism is rather different to that in an original 746. The circuit has 12 LDRs arranged in an array (3 columns, 4 ...
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200 LED through arduino via SN74HC595N shift register
I'm very new to any forms of multiplexing let alone electronics itself. From what I have researched, I can add more inputs/outputs to an Arduino via a shift register. I bought 10 SN74HC595N shift ...
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How to connect a large number of multi-throw switches efficiently?
I have a number of 7 pole single throw switches that I need to connect together in some sort of grid configuration to a microcontroller, while minimizing the number of pins on the micro and the number ...
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Charlieplexing 7-segment display segments vs segment
I understand the principle of charlieplex and the use of tri-state. What I don't understand is, can I light all segments on a display at once or do I have to light one segment at a time?
Say I have 8 ...
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For 12X8 LED array with any 1 LED glowing at a time, should we charlieplex or use 74HC595n?
Apologies in advance for probably missing a lot of things. I'm pretty new to electronics.
I'm building a 96(12X8) led (monochrome ultra bright, white) multiplexed array, driven by an Arduino nano. ...
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Arduino - Controlling 8 RGB LEDs (beginner question)
First time poster here.
I have an Arduino Uno project that will require 8 RGB LEDs to be controlled. They will be turned on and off with pushbuttons, cycling through red, then green, then blue, then ...
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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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How to debug a circuit that uses Charlieplexing and PWM with LEDs under ISIS?
Using mikroC and Proteus ISIS, I have built a circuit that uses a PIC12F629 (link to datasheet PDF). It controls several LEDs using Charlieplexing technique (and additionally PWM them to change their ...
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Need help understanding charlieplex circuit
I understand the principle behind charlieplexing, however I don't understand how the circuit below works. Say I wanted to illuminate LED5, wouldn't I set Pin1 to OUTPUT-LOW, Pin2 to INPUT, and Pin3 to ...
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Building a 3x3x3 LED cube?
I need to built a 3x3x3 LED cube. I need to be able to turn every LED on (not at the same time) in different patterns. I need to use Charlieplexing (note that any other method is not a viable option),...
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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 ...
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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 ...
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How to increase current drive of Charlieplexed LED array?
I am driving 15 LED's with a Charlieplexed circuit (using an Atmel ATTiny13). I've reached the current limit per I/O pin of 40mA and would like to drive the LED's higher (they're rated at 50mA).
Is ...
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Chaining limit for shift registers in large led matrix
I am thinking of trying to build a large led matrix in a way that is both modular and scalable (maybe up to around 100x100, or 500x16).
My thought is to make a single 8x8 module that I can make a few ...
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Charlieplexing different LEDs
I have four LEDS (red, green, blue, and yellow) and want to use charlieplexing to light them up.
I'll use an AtTiny13V which needs 1.8 to 5.5V. I think one CR2032 with 3V will be suffice for the µC.
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Charlieplexing Topology Question
I'm sitting here with a pencil and paper trying to arrange a charlieplexed 5x8 LED matrix. I'm trying to arrange this in such a manner that no two lines cross each other. Without a guiding theorem of ...
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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 ...
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CharliePlexing on a breadboard
I was making a breadboard demo for a Microcontroller class. Basically my project is to make a score keeping device. I want to drive 4 seven segment displays using an atmega8. I read about charlie ...
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