An LED is a light-emitting diode. Lighting an LED is considered the "Hello world" of a circuit design, and it can be as simple as putting a series resistor or can get more complicated, involving PWM and multiplexing.

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Could OLED displays be made to produce a voltage when off?

According to this guy it is feasible to use LEDs to detect light, because they will turn any light emitted on them into a tiny voltage that can be used in a sensor. Since modern flat screens (OLD) ...
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1answer
26 views

Proteus VSM: digital vs analog resistor and LED

I'm a newbie to electricity and electronics in general. I've been reading about the principles and have a basic understanding of them. I'm also diving into creating my first basic circuits with ...
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1answer
55 views

Led Driver/Controller for 3.3v & 5v circuit

PWM Circuit for 3.3v & 5v logic controllers @ high ampere With a 5m LED Strip (14.4W/m), a regulated 12v 10A power supply (120w) and lots of microcontrollers (Arduino Uno, Arduino Micro, ...
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2answers
85 views

smd resistor and regular through hole resistor

My question is fairly simple. I am building an SMD LED board and i am limited in space. So originally i was planning on going with through hole resistors, but have it being i'm very limited on space ...
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1answer
98 views

LED Shoes - circuit diagram ok?

I want to put LEDs into my shoes, specifically the Nike Air bubble (by drilling holes at the inside of the shoe and dropping them into the bubble). Im hoping to do it as cheap and as light as ...
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1answer
19 views

High power led driver for COB leds

I bought some chinese COB 100W Led lamps from Ebay and I was wondering what would be the most efficient way to power them. Led specifications: 24vDC 4.2A I want to use 4 leds in total, so that makes ...
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1answer
37 views

LED Display: Understanding Led pitch, resolution, viewing angle and distance

i'm working on project in which we need to design a Led Display. I google some information and get a little confused about some key topics. Some of them are: Led Pitch Viewing Angle Resolution ...
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2answers
85 views

How to build a continouous LED bar?

I would like to have something like an LED bar, except that the light emmission should not be broken up into separate lights, but be more or less continuous - without much greater light intensity per ...
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1answer
49 views

How to create an on/off indicator for a SPST in a circuit?

I've recently started to work with electronics and I'm truly a beginner. Our teacher asked us to create an on/off indicator for a SPST button in a circuit. When the button is pressed the green light ...
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3answers
386 views

Light LED light?

I would like to mount 10 or 20 white LED on a thin rod, about 2 m long - and around 3 mm in diameter. I will need to accept various compromises for conflicting requirements, but I try to understand ...
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2answers
68 views

Difference between 1W and 3W LED's [on hold]

I've come to the understanding, that heat is the killer for LED's, i.e. supplying a too high a current, the LED gets hot and dies. Now assume I have two LED's, 1W and 3W, both mounted on a heatsink. ...
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1answer
76 views

why my LEDs burned with the right driver?

I am trying to connect, in parallel, 18 LEDs that have these specs: LED size: 10mm; Voltage: 3.2V - 3.4V; Current: 20mA. Driver Type/Model: MeanWell LPC-20-350 (datasheet: ...
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1answer
42 views

P10 Outdoor RGB DIP LED Module

As I have to make driver for this matrix module, I have a big problem finding its schematic or datasheet. There are many similar modules on the internet, they are made in China. I'm making driver on ...
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2answers
76 views

How to design blinking LEDs circuit using analog elements only?

I want to design a circuit to blinking three LED in a row with 2 second delay for shifting/changing using analog elements only (using Resistors, Capacitors and Transistors and without Micro ...
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2answers
52 views

Can an IR transmitter be focused?

Can a transmitting IR LED (or an array of such devices) be focused into a finite area rather than allowed to spread out? I think this is how laser tag systems are implemented but I am not sure and I ...
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0answers
52 views

3V Coin Battery Charger

I'm trying to create a stable coin battery charger. I've checked a lot of topics but the closest answers are for 3.7V Li-Ion battery. I want to charge 3V Li-Ion Battery - MS621FE from Seiko (battery ...
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2answers
119 views

16 segment LED sparkfun resistor help

I am quite new to this and am struggling to read through the data sheets of the Sparkfun 16 segment display, datasheet here. I have managed to get all of the LEDs wired up through a LED driver, with ...
3
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1answer
96 views

555 fading in&out if possible with pwm & led array

i'm new here and also in the electronics world so pls be patient with my ignorance. I's now months that i'm fascinated by the 555 timer. The stuff you can do with such a tiny thing is impressing. ...
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1answer
55 views

Why does POT cause current to divert?

I have a pretty basic question. I put this little thing together but I don't understand why the POT is causing this result. When powered, if the POT isn't fully open. LED 1 is bright and LED 2 is ...
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1answer
54 views

Arduino LED Cube 8x8x8 with a Led Driver (TLC5940NT )

Me and a group of friends need to make a college project and decided to do a LED cube that can graph mathematical functions. We do not know how to code very well, and are very new to Electrical ...
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1answer
50 views

7-segment blue LED display at 3.3V

I'm driving a blue 7-segment LED display with a TI CD4026BE on a 3.3V circuit. I cannot find any data sheet for the display part. It has a common cathode pin layout and it's marked FJ5161AB on the ...
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0answers
25 views

What specs of power supply should I get for an IR controller for RGB 5050 LED strip?

Here's the story: Bought an LED strip kit (including 5M reel (150x5050 LEDs, rated at 36W), an IR controller, 12V, 2A AC-DC power adapter and a controller). The power supply failed after a few hours, ...
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2answers
54 views

Alternatives to Arduino for controlling LED's and Audio files? [closed]

Simple Alternatives to Arduino Has anyone used these different boards? If so, what did you use them for and why? Which are appropriate for controlling LED's and playing audio files? I'm looking ...
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1answer
52 views

Dimming an LED Strip (9v) with a 555 timer and MOSFET

I'm doing some VERY amateur prop building for an upcoming night of cosplay and I'm trying to create a throbbing/pulsing crystal for the top of a magic staff. Initially, I was just going to use a ...
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2answers
71 views

Best way to sync LED's to light NES figures on a wall clock?

Advice & Ideas needed... Working on a project - a custom wall clock with perler bead NES sprites in the place of the numbers. The figures are mounted to a wood board with cutouts underneath, and ...
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2answers
80 views

PIC16F877 blink program uploads correctly but nothing happens - hardware or software mistake?

I made a custom board based on a PIC16F877 but for now I only soldered the minimum. I installed MPLABX and the XC8 compiler, connected the ICD3 to the board, adapted a "blink" example to RD0 where my ...
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3answers
57 views

PIC16F676 - Is it possible to add a dimmer circuit to the seven segment displays

I am attempting to build a PIC16F676 based voltmeter using 3 multiplexed common-anode seven segment displays. Is it possible to add a light activated dimmer to control brightness of the displays ...
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1answer
39 views

Difference between dichroic, LED and halogenated lamps

I think that this isn't the best place to ask this, but I couldn't find my answer to this and I couldn't find any other stack exchange site related to this. I wanted to know the differences between ...
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2answers
35 views

ULN2803 not working properly in Proteous?

I'm trying to test ULN2803 with Led MATRIX. But with different Logic it is giving no change on the output and making the LED lit up. Why is this so
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2answers
64 views

Why does my mainboard power the cathode to turn the Power-LED off?

Close to all desktop motherboards have a pin header that is supposed to power an LED on the front of an enclosure with to indicate that the computer is on. In the documentation for my board, these ...
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1answer
30 views

LED organ input problem

I'd made this LED organ (schematic below and here): And one of the filters are not working. On the opamp's inverting input, there's a small sin signal, and I don't know where it comes from. I ...
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1answer
64 views

LED can't stop blinking (AVR-C)

So here is the basis of my code, I have an array of different instructions for the prescribed LEDs to follow. The led will blink for the prescribed number of times in an interrupt before they stop ...
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1answer
31 views

How do I model an LED with SPICE WITHOUT access to a Manufacturer's Datasheet

Looking to create a model of an LED (RL5-WW15030 from Superbrightleds.com): ...
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40 views

how to multiplex RGB LED without using drivers

how to multiplex 6x6x6 RGB LED cube without using drivers. I couldn't find drivers that I need. and I can't wait for it because of my competition. friend of mine who is senior told me to create my ...
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0answers
33 views

what LED driver to choose to drive the high power LEDs

I want to design a circuit with arduino and high power LED. so basically I have 10 red 1W LED , 5 1W blue LED, I want to control the red group and blue group respectively, moreover each group of color ...
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3answers
62 views

Light intensity is dropping on large LED bulb display when it sequences

I have assembled an LED display controller using an Arduino Mega 2560. The controller runs a display sequence on an array of (25) large LED bulbs that draw about 125 mA each. It also has a smaller ...
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0answers
33 views

BeagleBone Black LED current/brightness

I'm in the process of designing a PCB that includes 10-15 LEDs. It's battery-powered, so I'd like to use as little power as possible. As such, I've been trying to figure out how little current the ...
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2answers
63 views

explanation of the LED circuit

I just brought a LED board with 220V AC from here http://www.amazon.co.uk/Enjoydeal-Hydroponic-Plant-Light-Panel/dp/B00V5Y2FWG I looked inside the board, and am curious about how so many LED are ...
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1answer
67 views

Another motorcycle project: gear selection indicator [closed]

I have another little project that I have been thinking of making, but am having some trouble with the circuit design. In a nutshell, here is what I am envisioning: Objective: Create an electronic ...
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2answers
81 views

Want LED to stay on once it is triggered

Have built the Seattle Univ cell phone detector to locate hidden harassment devices around my home, especially the auto tracker presently installed somewhere in my car. Circuit works well, and LED ...
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1answer
129 views

LEDs driver circuit

I was wondering what is the role of this type of circuit connected to LEDs. I found it in a LED torch supplied by 2xAA batteries. Is it an oscillator? Is it only an energy trick? What are the ...
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1answer
61 views

Can use 17 resistors with 16 rgb led's?

I always see an rgb led ran with 3 resistors, for example a 20ma led on 5v power uses 150ohm's for red due to it's lower voltage but only 100ohms for green and blue. I am running 6 shift registers off ...
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4answers
119 views

Photodiode - Turn Digital Input pin into 1 with little light Input

Currently I am trying to work with a photodiode(SFH 203) that is supposed to detect very small amount of light. Using the digital of an arduino the photodiode cannot turn the pin to 1 due to the low ...
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2answers
87 views

LED lamp increased power consumption after installation: Why? [closed]

I'm new here, but I've been checking your forum few times before, never registered. Anyway... I have a problem at my home. I'm not very electrical kind of guy, so these questions may be easy to answer ...
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0answers
31 views

Remote LED dimmer

I have a question about LED dimmers. I'm using a 12v-24v LED single color remote dimmer with a Output Power: < 96W & rated Load Current: < 8A, it was working with a lower powered LED but ...
17
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3answers
1k views

What are the 'knuckles' on through-hole LEDs and photodiodes for?

I am using an IR LED and a photo diode, and I have designed the PCB according to the specifications that I found on the datasheet - i.e. hole sizes for the pins being 0.6 mm. However, on these ...
4
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1answer
43 views

How does area and intensity relate to perceptive brigthness of a light source?

I want to design tail-lights for onboard use in vehicles (mostly bicycles), but I wonder how should I configure the system so as to get the best visual perception from a distance. Each lighting ...
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3answers
91 views

Removing flickering of LED lightning

I am trying to install recessed, dimmable LED lightning in the living room. We're talking about an end solution of maybe 15-20 spot lights. My home has 120V/60Hz. Currently I am experimenting with a ...
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2answers
59 views

LEDs and External Quantum Efficiency (EQE), how to find Light Output Power with test results? How to find power?

I'll try explain everything as clearly as I can as it's slightly complicated. I really need help as I'm quite new to this kind of experiment and work so any help would be extremely appreciated. I did ...
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1answer
41 views

No output from programmed attiny2313

I flashed a simple led blink program to an attiny2313 with a usbasp type programmer. Avrdude confirmed that the chip was programed, but the led is not blinking. I tried switching the led, varying ...