Questions tagged [dimming]

'dimming' is the action of reducing the amount of light emitted from a device.

Filter by
Sorted by
Tagged with
-1 votes
1 answer
57 views

Is there anything to limit LED output dimming 50% while the wall dimmer controls 50% to 0%?

We got a project for a client but our lights are too bright for the space, we still want to sell the the lights because we have extra inventory and need a way to dim the LED output to 25W instead of ...
user avatar
  • 1
1 vote
1 answer
131 views

How to drive multiple floating N-channel MOSFETs

I want drive a RGBW-LED (CREE XLamp XM-L) using a synchronous constant current buck. To control the brightness and color, the LED of each color channel is controlled by a shunt transistor using PWM. ...
user avatar
  • 255
0 votes
1 answer
90 views

Nixie anode transistor dimmer

I'm working on my nixie clock (IN-14) and I am stucked on one problem. When I tried to dim my nixie tube through transistor on cathode, everything works fine. simulate this circuit – Schematic ...
user avatar
0 votes
0 answers
50 views

noise based dimming of an LED

I am thinking about building a dimmer for an LED that does not use PWM. My idea is to use a white-noise-signal and switch an LED on (or off) depending on whether the signal is above or below a certain ...
user avatar
  • 101
-1 votes
4 answers
186 views

Why is the transistor in this dimming circuit getting very hot?

This is a fairly simple dimming circuit using a dual opamp (IC1) as a comparator to control the brightening and dimming of a light bulb. The switch (pin 2 IC1a) is a contact connection to ground. ...
user avatar
  • 181
-1 votes
3 answers
115 views

Need advice on an LED dimmer 0-10 V circuit

I've setup a small system where I can control a 6 W LED. I change the brightness of the lamp by adjusting the signal 0-10 V. Diagram (2) is the waveform while connecting with a phase-cutting dimmer ...
user avatar
  • 91
0 votes
1 answer
71 views

How to limit voltage to microcontroller, and drain the rest?

I am designing a circuit to control a set of 0-10v dimmable lights. The lights have two lines, Dim+ and Dim-. Dim+ will be at 10 volts, and the brightness is controlled based on how much is drained to ...
user avatar
0 votes
1 answer
82 views

I don't understand dimming on 3 quadrant TRIACs

Can someone help me understand how dimming works on 3-quadrant triacs? I understand they are great because they have higher reliability and don't need snubbers. What I don't understand is how 0-100% ...
user avatar
0 votes
1 answer
53 views

Phase cut dimming driver for panel lights having occasional flick

I am designing a phase-cut dimming driver for Incandescent bulbs as well as LED panel lights with dimmable drivers. Using a BTA24 Triac and VOT8121AB Optocoupler driven by my MCU. For zero-cross ...
user avatar
1 vote
0 answers
59 views

Uneven Brightness Curve When Using Digital Triac Dimmer on Neon Transformer

I am working on an AC dimmer project using the following circuit: This circuit functions by detecting zero crossings in the AC power input via the LTV814 optocoupler connected to a pull-up input pin ...
user avatar
0 votes
0 answers
73 views

RC PWM question - dimming LEDs

I have some automotive LEDs that I put onto an RC car. I use the RC car's 4S LiPo (14.8v) to power the LEDs and they are great. I use a hobby PWM relay board to turn them on and off and that's slick; ...
user avatar
1 vote
0 answers
68 views

LED driver/analog adjustable constant current source with constant output without PWM switching?

I am using 3 halogen lights with 5V/0.5A each controlled by a constant current source (or basically "LED driver") because of light accuracy. Right now I am using the PT4115 (step down led ...
user avatar
  • 365
0 votes
2 answers
55 views

Dimming energy with load cell

I'm a lawyer with no technical background. I'm just a geek! :D I wonder if it is possible without using a micro controller can a load cell dim the amount of energy supplied by a 3V battery? The ...
user avatar
  • 103
0 votes
0 answers
68 views

Is there a way to dim CCFL lamps in a monitor backlight?

I use 30 inch monitor Samsung 305t that uses 16 CCFL lamps as a direct backlight. The driver consists of 8 HV transformers, each of them running 2 lamps in series. Some info about the lamps: As you ...
user avatar
  • 123
0 votes
1 answer
213 views

How does amplitude dimming (CCR) work?

When a LED driver dims using constant current reduction (CCR), what voltage and current is sent to the LED chip at the various dimming levels? Say I have a CCR-compatible LED chip which takes 500mA ...
user avatar
  • 105
0 votes
1 answer
182 views

Can a Triac be driven using only positive voltage due to the laws of Q1 and Q4 quadrants?

I have a BTA12-600B Triac and an Arduino. Is it possible I can trigger both positive and negative amplitudes of an AC cycle by suppling only a positive voltage from the Arduino digital pin to the ...
user avatar
  • 1
3 votes
0 answers
90 views

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 ...
user avatar
  • 836
1 vote
1 answer
338 views

MeanWell PWM dimming

I have similar situation, described here: MeanWell 3-in-1 dimming So, I need to control MeanWell power by PWM signal from Arduino. I tried to simulate scematics, given as answer in that topic, but it ...
user avatar
  • 9
3 votes
2 answers
403 views

Getting problem in triac based fan speed control

I'm using this circuit to control the speed of ceiling fan. The fan speed is divided into 8 steps. (0:off & 8:full speed) with 100us gate pulse. This circuit works with incancescent light bulb ...
user avatar
0 votes
1 answer
507 views

Trailing edge dimmer circuit limitations

I just came across this circuit meant for trailing edge dimming of LED bulbs but I was wondering what else could it be used for and what its limitations are during general use. To my understanding by ...
user avatar
  • 25
0 votes
0 answers
46 views

Advice on controlling an unknown dim-able 12V LED

I have been controlling "5050" RGB LED strips from the GPIO of a Raspberry pi with a simple circuit using mosfets. This is the guide that I followed: https://dordnung.de/raspberrypi-ledstrip/...
user avatar
  • 11
0 votes
1 answer
31 views

is connecting high end high power leds in series feasible and are there light quality or other issues

i'm building high power high CRI cine lighting mostly to illuminate softboxes and have chosen Cree XLamp CMT2850 LED 1400mA 36V (Fidelity 95plus CRI). I plan to build about 12 units for the studio. I ...
user avatar
1 vote
1 answer
36 views

Step up regulator with fading input

I have an input power source that fades an LED on and off smoothly, from 0 volts to 7.5 volts. I would like to use a 12 volt LED. I have been looking at step up regulators which look suitable for ...
user avatar
0 votes
4 answers
234 views

Powering 12V 35W halogen bulbs with a constant current supply

I'm revisiting an old project, and I want to see if there is anything I could have done differently, or if I missed any important details or considerations. Basically, I used a constant current driver ...
user avatar
0 votes
2 answers
63 views

How is Gate Trigger Current determined in a "dimming" circuit?

EDIT: DIAC part numnber is DB3TG I'm trying to understand how a dimming circuit works, specifically TRIAC control. The TRIAC (D1) in this circuit is a BT136S-6. Where does the Gate Trigger Current ...
user avatar
  • 207
1 vote
1 answer
481 views

Christmas LED dimming circuit with potentiometer

I need help. I would like to dim LEDS of a Christmas tree with a potentiometer. Here is my electric diagram. (Please note I'm a beginner in electronics.) I don't know how to choose a good value for ...
user avatar
  • 31
4 votes
2 answers
391 views

Can this WWII era rheostat be modified to dim an LED bulb?

I have a WWII era RAF chart-board lamp in perfect unused condition. I want to use an LED bulb with the original dimmer as tungsten runs so hot. I want to avoid rewiring or bypassing the dimmer as the ...
user avatar
3 votes
4 answers
1k views

How to dim one of these cheap 5mW laser modules?

I used to have an old 3x LR44 lithium cell laser pointer for presentations. With the batteries slowly dying, the outputted beam also went dimmer. Recently I bought one of these cheap 650nm laser ...
user avatar
  • 275
1 vote
2 answers
58 views

How to adjust the brightness of a small LCD(21V) with a potentiometer?

I want to adjust the brightness of a small LCD with a potentiometer. How can I use a 555 timer to make a PWM which can give out an output of 21V from a 5V input?
user avatar
  • 3
2 votes
1 answer
681 views

Why does color of addressable RGB LED strip change when dimming?

TL;DR I have an addressable LED strip with TM1814 IC's. (So it's actually a RGBW strip. Download datasheet here.) When set to orange at full brightness, it's orange. But when set to orange at 10%, it ...
user avatar
1 vote
2 answers
489 views

Meanwell Led driver: internal 3-in-1 dimming circuit

In Meanwell led drivers like the ones from the XLM, HLG or LCM families, how does the internal circuitry for the 3-in-1 dimming feature (0-10V, 10V PWM, 0-100kOhm) look like? I use a LCM-25 in my ...
user avatar
  • 2,394
1 vote
2 answers
118 views

Pulse Dimming to 1-10V

I have a question about the dimming of Led drivers. I have a lot of LED drivers which can use pulse dimming or 1-10V dimming. One problem I have is that I realized too late that by using pulse dimming,...
user avatar
0 votes
2 answers
514 views

Adjustable current source 0-20mA for LED dimming

I have been searching through the site, but I have not been able find an answer. I have an LED (rated for 14 mA at 24V, the LED is with built-in series resistor) that I need to be able to dim from ...
user avatar
  • 65
1 vote
2 answers
325 views

Building a passive Dim-to-Warm LED array

I have started a project for my home lighting, I'm trying to build a DC LED module which would change the color temperature from 3000K to 1800K as dimmed with reducing current. I'd like to do it ...
user avatar
0 votes
0 answers
53 views

Need help in zero cross circuit by using op-amp

I worked on zero crossing circuit by using opto-coupler.Circuit is It is working okay.Zero_crossing signal is There is a 2-3 ms of signal loss is happening with 50Hz of AC signal.I don't want more ...
user avatar
  • 21
1 vote
1 answer
300 views

Need help understanding the MOSFET trailing edge dimming

I am working on a circuit to control AC loads up to 1.5 kW by using MOSFETs (FCHD125N65S3R0-F155). The circuit: I have a few concerns: The current is flowing through the body diode of Q2 during the ...
user avatar
  • 21
2 votes
1 answer
759 views

How can I dim 50 high-power LEDs in series with an Arduino?

What I'm trying to do is to use an Arduino to control the brightness of two series of 50 high-power LEDs independently. Each series has an independent LED driver, and each LED has a foward voltage ...
user avatar
-1 votes
1 answer
324 views

Motion triggered battery powered dimmable COB LED light

My view on life, in any field, is not to produce more but to consume less. Everybody told me this is a very eccentric weird mentality. Perhaps they are right. Nevertheless I have to build my project ...
user avatar
0 votes
1 answer
157 views

Limiting the Current of a Constant Current LED Driver which is Driving a Halogen Bulb

I am powering a 12V, 35W halogen bulb with a MeanWell HLG-100H-20B constant current power supply. The "B" version of this power supply has a really neat dimming control system which lets one control ...
user avatar
0 votes
1 answer
60 views

Dim a 110 Light using 5v PWM with no ZC

I was wondering if anyone has any ideas of a way I could Dim a 110v Halogen light with the use of 5V PWM, or with 0-24v control. My controller, has the basic (designed) 0-24v control. It also has ...
user avatar
0 votes
1 answer
125 views

fan speed regulation causes other loads flickkering

I am using traic based dimmer circuit for regulating my ceiling fan. when the fan is regulated to low speed the other loads(incandescent,tube light,LED) in the room are flickering. when i increase the ...
user avatar
0 votes
1 answer
905 views

AC dimming with STM32 timers

I'm using an STM32 for AC dimming, for which I use a GPIO output (or timer channel out) to drive a triac, whenever I get a zero crossing detection (rising edge). Is there a way to solve this only ...
user avatar
16 votes
9 answers
5k views

Cheap and safe way to dim 100+ 60W Incandescent bulbs

For my wedding reception, we are building ~25 lighting fixtures with 4 bulbs each (fixture per table for dinner). For aesthetic and budget reasons, these are 60w "Edison-style" bulbs which we want to ...
user avatar
0 votes
0 answers
303 views

RFI filter modeling in LTspice w/ triac

I have a few questions about modeling an RFI filter in LTspice with a triac-based dimmer circuit. I'm referencing the circuit described in Figure 11 in Triac Principles and Circuits -- Part 2 (Nuts &...
user avatar
  • 333
4 votes
1 answer
2k views

MeanWell 3-in-1 dimming

I've got a constant current MeanWell LED driver that has 3-in-1 dimming (100k potentiometer, 0-10V signal or 10V PWM), and would like to control the dimming with a microcontroller. I found a few ...
user avatar
1 vote
1 answer
232 views

LED Driver, Turning ON/OFF consistently

I am building an array of LEDs that I plan to power up with an LED driver. Here is the one I chose - Mean Well LCM-60U I have been using it and it works great. However, I have one thing I am trying ...
user avatar
  • 121
2 votes
3 answers
365 views

Dim LED lamp with constant current power supply using resistors

I own a really bright led lamp that I want to dim. It is powered by a constant current power supply that can supply 37mA between 11V to 17V. If my lamp is connected the voltage settles at 13.58V. ...
user avatar
  • 41
7 votes
3 answers
1k views

Glitch in AC sine wave interfering with phase cut dimming

My company installs ZigBee-based phase cut dimmers for bulbs and LEDs (those which support phase cut dimming). Recently, we encountered a site where we faced a flicker issue. The light is slightly ...
user avatar
  • 7,532
0 votes
1 answer
189 views

How much battery power for LED and how to make it flicker [closed]

I am trying to figure out what configuration of battery(ies) I need to power this LED. I am only using one (specifically the warm white 1-up). I am also looking to make it flicker like a candle with ...
user avatar
  • 21
-1 votes
1 answer
69 views

Lamp is dim for ages when turning on straight after turning off [closed]

My bedside table lamp is plugged into a powerboard and is using a 9.5W Mirabella LED bulb on a 240V circuit - in Australia, i.e. with the Australian plugs. We can't buy incandescents here as they are ...
user avatar