Unanswered Questions
666 questions with no upvoted or accepted answers
4
votes
0
answers
374
views
Ultra-fast driver circuit for low-power LED
The goal is to drive a low power LED at a very high frequency, with pulses of ~10-100ns width in order to produce a very narrow burst of light. The pulses do not need to be closely packed together, ...
- 41
4
votes
2
answers
103
views
Photodiode square wave positive duty cycle lower and lower
I drive an IR LED with a 50% duty cycle square wave and receive its signal with a photodiode. If I take the photodiode farther and farther from the LED, the signal's positive duty cycle is lower and ...
- 17k
3
votes
0
answers
79
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Modding a $30 fog machine, driving high power LEDs?
I've recently acquired a $30 fog machine off Amazon that features, next to the obvious fogger, eight high power RGB LEDs, controlled in series via a RF remote. The LEDs are very bright so I assumed ...
3
votes
0
answers
104
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How to interface buzzer with LED in this circuit
Below is the circuit where I want to integrate the buzzer with the red LED.
The task is to add the buzzer, where the red LED is, in such a way that when the red LED (which is driven by the LED driver)...
- 31
3
votes
0
answers
185
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New driver/controller for Christmas tree LEDs
I have a 600-LED Christmas tree. The controller went kaputt.
The tree consists of three sections with two groups of lights in each section. The LEDs themselves are a two-lead type RGB and have two ...
- 31
3
votes
0
answers
96
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How to indicate an android tablet is actively charging with LED?
I am a rank beginner, and I do feel like I am missing something pretty obvious here, as the problem doesn't seem that complex. (I know... famous last words)
Problem:
Android tablet (in a completely ...
Null♦
- 7,623
3
votes
0
answers
2k
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Why does my lamp say "Use max 60 watt Type A OR max 10 watt LED?"
I'm really intrigued by the label on a new lamp. It says:
Caution: To reduce the risk of fire, use MAX 60 watt type A lamp OR use MAX 10 watt self-ballasted LED lamp or lamp adapter.
Now I didn't ...
- 177k
3
votes
0
answers
96
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How to prevent LEDs from flashing when turned ON
I have a custom board to control multiple high-brightness strip LED (ON/OFF and dimming through a potentiometer).
Into this board, I have some strip LED that are continuously ON (only dimmable) and ...
- 15.7k
3
votes
2
answers
102
views
Boosting load current of voltage regulator
I'm trying to connect little 3v LEDs to a motorcycle's alternator and i want to regulate the voltage of it to 3 volts so the LEDs don't burn up
the alternator gives off 2.5 volts and over with 3 amps ...
- 172
3
votes
2
answers
171
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Wind-powered fairy lights + battery charger: preliminary help
I'm new here and asking for help designing a yard-art project. I would like to use a small DC motor as a wind-powered generator to charge a battery (with overcharge prevention) and run some battery ...
CommunityBot
- 1
3
votes
0
answers
291
views
7030 SMD LED pad configuration
I have not done a lot of work with SMD LEDs and have a question about the pad layout. I have done quite a bit of research and haven't found much helpful info yet.
I am working with 7030 SMD LEDs ...
- 711
2
votes
0
answers
34
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Flashing STM32h562ZI (on NUCLEO-H563ZI board) using μVision5
I am trying to make a project with NUCLEO-H563ZI in μVision5, starting simple with opening the embedded LED on the board.
main.c:
...
- 163
2
votes
2
answers
104
views
Circuit that turns on an LED and turns it off after some time
I want to create a circuit that turns on an LED when a switch is flipped and automatically turns it off after some time. I use a capacitor for the timedelay.
Because I want it to be able to be reused ...
- 31
2
votes
1
answer
159
views
ESP8266 + MOSFETs + LED strips
I'm trying to drive with PWM the usual 12V LED strip with a WeMos D1 Mini and a bunch of MOSFETs.
Here's the circuit:
What do you think of it regarding MOSFET choice and resistor placement?
Edit (...
CommunityBot
- 1
2
votes
0
answers
99
views
Determining if white LEDs are eye safe for direct eye exposure
I am looking at buying lots of LEDs for a signboard hobby project. This is my first project using LEDs and I wanted to make sure (and learn) that I am making a safe project.
The LEDs I am looking at ...
- 303