All Questions
Tagged with buck led-driver
33
questions
1
vote
1
answer
67
views
PI filter for two buck drivers for a low-emi solution
I'd like to save space on a circuit that uses two buck LED drivers. The circuit is designed for a low EMI solution and there are two separate PI filters on each Vin pin (recommanded on the datasheet). ...
- 83
3
votes
2
answers
80
views
Current peak on a low EMI buck LED driver
I'm designing a buck LED driver using the LT8376 and I'm following the typical application for a low EMI solution (page 26).
On the output, the schematic proposes a 100 nF capacitor in parallel with ...
- 83
4
votes
2
answers
764
views
Please offer comments, critique on self-resonating invented buck joule thief converter for third world use [closed]
Even though I'm not an EE, I have simulated the Joule Thief to death in LTSpice, but I have not yet made a prototype of this circuit. I have a friend who is an EE who won a contract to light some ...
- 2,892
0
votes
0
answers
73
views
How to make a hight power strobe light (ACL) with arduino and high power LED
I'd like to make a high power strobe anti collision light (ACL) for aviation.
The available power source is 12 - 13 V DC.
The strobe pattern should be programmable / adjustable, therefore an arduino ...
0
votes
1
answer
89
views
STCS05DR LED driver
I am trying to use the STCS05DR constant current LED driver IC by STMicro in my buck converter design to indicate input power with a 1206 red LED.
The input power is a variable DC battery source (...
0
votes
1
answer
378
views
How to remove 200 mV ripple from my power supply? [closed]
I am using a step-down-converter to get a variable supply output in the range of 2-4 V from a 5 V input voltage from an adapter.
The problem I am facing is that I get a 200 mV ripple which looks like ...
- 65
1
vote
1
answer
494
views
Sanity checking an LM2596-ADJ constant current supply design for driving LEDs
I've designed, in simulation, an adjustable constant-current supply based on an LM2596-ADJ buck converter IC.
I chose STW8B12C LEDs for simulation because three of them in series roughly matches up ...
- 10.8k
1
vote
2
answers
76
views
Improve thermal effeciency of buck LED driver with fixed supply rail
I have this driver circuit that uses an ILD8150:
There are two identical sections of this module on my PCB.
One powers 6 LEDs the other powers only 2 LED. The Vf of the LEDs is 2.85V @ 350 mA.
So the ...
- 1,235
0
votes
0
answers
68
views
Question on resistor voltage dropper values for VCC supply of LED driver IC
I was designing the PCB for a 10 W LED driver with the AL1676 controller. From the datasheet, the application circuit shows that the driver takes its VCC supply through R1 and R2. The maximum value ...
- 1
0
votes
1
answer
97
views
Inductor position in low side buck converter
I am designing a PCB to control an RGBW-LED. To provide a regualted current for each color I am using the LM3407 buck converter from TI. The buck converter is powered with 12V and is configured to ...
- 285
1
vote
1
answer
71
views
TPS9264x Synchronous Buck Controllers for Precision Dimming LED Drivers
I have some questions about TI's TPS92641.
Please see below:
1.) Does anybody know the principle of Chopper OTA? there are no too much information in the datasheet.
2.) What's Quasi-hysteretic ...
- 413
1
vote
2
answers
234
views
What power supply do I need for this LED driver?
I'm putting together a project where I'll be driving 4 x 10W RGB LEDs (these ones) with one PicoBuck LED driver. I'll be using all three channels on the LEDs at the same time and controlling dimming ...
- 19
1
vote
1
answer
1k
views
What is the difference between buck and step-down converter
I always thought "buck" and "step-down" are synonyms. But now I'm looking at two datasheets:
CAT4201
CAV4201
They seem very similar, but the first is described as "350 mA ...
- 1,235
1
vote
0
answers
148
views
Calculating constant current buck converter ripple current
For building a constant current LED driver, I'm looking at the TI LM3407 datasheet: https://www.ti.com/lit/ds/symlink/lm3407.pdf
For calculating the necessary inductor, there's several things I don't ...
- 111
5
votes
1
answer
690
views
36x LED 5730 in series: diodes burnt when LED driver (based on BP9833A or MT7854BD) powered up
Background:
I have 18W, 36 LED lamp fixture which I cannot change.
Originally it has 2x parallel 18off 5730 LEDs and 300mA driver. It works for some time, but diodes starts burning. I thought that ...
- 61
0
votes
0
answers
259
views
Help refining a current control loop circuit
As a follow up to this question. (Sorry if this linking other posts is wrong. I'm new to forums)
Will this design for an XHP70.2 LED Driver with arduino control work to the params specified?
TL;DR: ...
- 69
0
votes
1
answer
214
views
Buck convertor calculation on Vout close to Vin
I'm currently stuck in calculating the right inductor for driving very bright LED's with The TPS92518 led driver. (http://www.ti.com/product/TPS92518-Q1)
This is a 2 channel LED driver and on every ...
- 143
4
votes
4
answers
514
views
Multiple switching LED drivers on single PCB
I am working on a high power LED board project. It requires to have 100 LEDs, of different types and colors. There will need to be 17 individual strands (need to be able to dim them separate.) Max ...
- 736
5
votes
2
answers
492
views
Open-loop Buck LED dimming
About this buck LED driver...
TL/DR the questions:
1) I intend to drive the FET from a microcontroller PWM via a suitable FET driver. This open loop control scheme seems too simple. Is it a trap? I ...
- 79.5k
3
votes
3
answers
425
views
Setting current on Diodes Inc PAM2863 LED driver IC, with external resistor AND driving different voltage to VSET
I'm looking to use the Diodes Inc PAM2863 DC-DC LED driver in a project.
The datasheet gives a V=IR method for setting the average output current with an external resistor, where Iout = 0.1 / Rs.
...
- 31
6
votes
3
answers
937
views
Reduce output current ripple on hysteretic buck converters
I am learning to use a new type of regulator: a buck with hysteretic control, therefore with no fixed frequency and no output capacitor.
As example, I was trying out the ILD4001 for an LED driver. ...
- 1,305
1
vote
3
answers
350
views
LED buck driver
I'm trying to build a 1A LED buck
It works well, current in leds depends of pwm duty until 1A and more, but when I watch signals with an oscilloscope, there are noise or oscillations on Rsense.
See ...
- 71
1
vote
3
answers
178
views
Is there anything wrong with my current setup for LED
I'm planning on building my own 5W high power LED Lamp, and this is my current setup:
Circuit
My power source is going to be 3 Li Ion Batteries in series, giving 14.8 volts for most of the time.
I ...
- 43
0
votes
2
answers
632
views
Why my boost converter is not boosting the voltage?
I am trying to build a boost converter using LT3517 with 5V input. LED and input voltage(5V) is constant for our application. I need to tune the circuit between this and the current across the LED ...
2
votes
2
answers
1k
views
Why is the efficiency of this LED driver circuit so low?
I created an LED driver board based on PAM2863ECR http://www.diodes.com/_files/datasheets/PAM2863.pdf
The board includes three identical driver circuits to drive three LEDs. I'm not able to wire the ...
- 2,177
1
vote
0
answers
3k
views
PT4115 LED driver
Excuse me if my question is too specific. I'm trying to get an LED driver using PT4115 work. I've spent hours but no success. I've created exactly the circuit depicted in the datasheet.
I have used 0....
- 405
0
votes
1
answer
8k
views
LED bulb can not start properly (BP2832 based)
I bought several LED bulbs about 2 years ago, and now before turn LEDs steady on, some of them flash for some time. Frequency of flashing may differ from bulb to bulb. After some time flashing, they ...
- 7,120
4
votes
2
answers
824
views
Can overshoot current from DC/DC converter damage LED lamp?
I'm building buck converter to drive led lamps. It consists of microcontroller, PWM generator, buck-circuit and current sensor. Microcontroller knows what target current should be and sets duty cycle ...
- 395
1
vote
1
answer
244
views
Buck Boost Driver to switch 2 LED chains
simulate this circuit – Schematic created using CircuitLab
I'm working on a project to turn 2 LED strings (each containing 6 HB LEDs).
Here is my question.
The Buck Boost driver I'm using is ...
- 161
0
votes
1
answer
117
views
LM3405 (buck driver) dropout
I've built an LM3405 LED Driver, which works (seem) well. The LED have a 3.2V of Vf and works at 700mA. The regulator uses an external boost voltage of 3V (from an LDO). Reading the datasheet of the ...
- 1,305