An LED driver is a self-contained power supply that controls the amount of current and voltage supplied to an LED light. An LED constant current driver monitors the loop current of each LED and automatically adjusts the generated DC voltage output to the minimum value needed to produce the highest forward voltage. As mains power is AC and Light Emitting Diodes run on DC, this current needs to be converted by a rectifier
Questions tagged [led-driver]
854 questions
157
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How can I efficiently drive an LED?
I understand that I can not connect an LED directly to a battery because it will draw too much current. Thus, there must be something else in the circuit to limit the current.
What options are there? Are some methods more efficient than others?
Phil Frost
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The mysterious case of the random leakage current
Disclaimer: I already know the solution of this circuit debugging conundrum (and it is not trivial), and I'll post it after some time, so that other people could give their contribution to this mystery story! I think it may have some educational…
LorenzoDonati4Ukraine-OnStrike
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LM2586 - Inductor Heats Then Burns
I'm designing a step-up constant current source to drive LED strips (nominal load voltage is about 54 VDC). Requirements:
Vin: 18..32 VDC
Iout = 0.2 A
Vout = 54 VDC (nominal) - 57 VDC (maximum)
Since the circuit should have an on-off input, I…
Rohat Kılıç
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Why do most flyback converters / LED drivers operate under 100 kHz?
Most of the LED drivers and flyback converters I have come across operate in the 60-100 kHz range. Is there any particular reason behind this - example - ferrite cores not being able to handle higher frequencies, etc.?
Regular buck converters go up…
Whiskeyjack
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Why did my LED drivers blow up?
I recently designed my first PCB, which houses LED driver circuitry for some custom lighting. I fastidiously followed the driver's datasheet (Diodes Inc AL8862QSP-13) in designing the circuit: making sure the inductor, capacitor, current sense…
Reid
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How to drive 700mA LED cheaply?
I'm new to electronics and am trying to make a night vision circuit. A similar question has been asked before, but with priority on efficiency. I want to control a 700mA-1000mA IR LED using a 5v input and an ESP8266 microcontroller as part of a…
maurera
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Are LEDs in modern streetlights usually pulsed? If so, roughly what frequency?
I can think of some reasons why modern LED streetlights would likely be pulsed;
Efficient voltage conversion starting from line voltage would likely include an AC or switching step higher than 60 Hz.
Highest efficiency operation of LEDs often…
uhoh
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Hacking a cheap DC-DC buck converter module (LM2596 chip) into a CC LED driver
On the Internet you can find plenty of dirty cheap DC-DC buck converter modules like the
following:
which is based on an LM2596-ADJ SMPS IC and follows the schematic in the application notes of
the manufacturer:
On the other hand, switching…
LorenzoDonati4Ukraine-OnStrike
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Explanation of LED driver circuit
I've been reading up on LED drivers and found some common connection schemes. Yet, I recently came across the following LED driver circuit at this URL:
I tried to find out what exactely was going on here but I do not understand why the LEDs are fed…
Tom L.
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Can I send PWM through 1 meter cable?
I am working on a project where I need to drive two LEDs on a PCB (= PCB_LED) which is 1 meter away from another PCB (= PCB_MCU).
The PCB_MCU includes a microcontroller with two LED drivers. Each LED driver is a constant current buck driver. Its…
JackOfHearts
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7
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3 answers
High power (up to 400W) LED DC/DC power supply design considerations
I am designing a power supply for a high power COB LED requiring 360W @ ~75V from a variable ~60-80V DC input. I have noticed that it is difficult to find switching controller ICs that advertise being able to operate at such high power outputs, and…
nebkat
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7
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LED-driver board with WS2818/WS2811 and PT4115
I want to develop a board with a WS2818 IC and three PT4115 as high current LED drivers. Input voltage shall be 12-18V. You can easily mount a Wemos D1 Mini ESP8266 board on the top edge, as the pins are in the right positions. The output current of…
Spatz
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7
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Microcontroller Adjustable 2A 24V Constant Current Source
I need to come up with a method to provide a microcontroller-adjustable, regulated current ranging from 0-2A at ~24V to a load in a closed-loop fashion. I have been researching this issue for awhile and have found a few ways that it could be…
carpenma
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6
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What is the use of the PNP transistor in this circuit?
The schematic below describes the structure of a single channel from the 8-Channel Darlington Current Driver TD62783A.
Image source: 8-Channel Darlington Current Driver TD62783A
I understand most of the circuit's workings but I fail to understand…
Virgil_Tibbs
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6
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Is the output of a 12V DC driver different depending on forward or reverse phase AC input?
Does the output of a 120 volt AC to 12 volt DC LED driver differ depending on whether it receives forward-phase AC input or reverse-phase AC input from a dimmer?
I’m curious because I have some LED lamps that are failing prematurely and some that…
Edward Ocampo-Gooding
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