Sonsivri
 
*
Welcome, Guest. Please login or register.
Did you miss your activation email?
December 08, 2016, 11:00:28 23:00


Login with username, password and session length


Pages: [1]
Print
Author Topic: High Powered LED - PWM Controlled Circuit - Suggestions  (Read 2953 times)
0 Members and 1 Guest are viewing this topic.
ikefu
Inactive

Offline Offline

Posts: 3

Thank You
-Given: 4
-Receive: 0


« on: September 15, 2013, 12:13:40 00:13 »

Hi all,

I'm working on a light controller board for a laminar fountain project. I need some help getting started figuring out how to drive a high powered LED (1 Amp+) utilizing a PWM signal from a PIC18F26K22.

Most of the circuits I have found either don't allow for PWM dimming or don't support the current output I need. If anyone has some suggestions to point me towards certain ICs or schematics I would greatly appreciate it.

Extra info:
I'm using this to add RGB lighting effects to a Laminar Fountain I built a few years ago and recently resumed working on. I'll be feeding the light output into fiber-optic cable that carries the light to base of the water nozzle. The high powered LEDs are required to light the entirety of the stream.
You can find my fountain here: http://laminar.forumotion.com/t162-ike-s-prototype-project-my-first-laminar-nozzle  That forum is a great resource if you are interested in building a laminar forum.
Logged
Gallymimu
Hero Member
*****
Offline Offline

Posts: 579

Thank You
-Given: 101
-Receive: 151


« Reply #1 on: September 15, 2013, 01:21:09 01:21 »

I've done this with 300mA using AP8800 from Diodes inc.

you should be able to find a 1A+ buck regulator that can do this (assuming you are starting with a higher voltage).  Either PWM the enable on the regulator, or set the current with a filtered PWM to get a roughly analog setpoint.

this IC will work for instance:
http://www.allegromicro.com/Products/Regulators-And-Lighting/LED-Drivers-For-Lighting/A6211.aspx
« Last Edit: September 15, 2013, 01:27:18 01:27 by Gallymimu » Logged
Old_but_Alive
V.I.P
Active Member
*****
Offline Offline

Posts: 211

Thank You
-Given: 154
-Receive: 56


« Reply #2 on: September 15, 2013, 03:34:30 03:34 »

I design LED lighting for a living, and Linear Tech have many suitable IC's

http://www.linear.com/products/led_driver_ics
Logged
dezso
Junior Member
**
Offline Offline

Posts: 80

Thank You
-Given: 29
-Receive: 137


« Reply #3 on: September 15, 2013, 05:03:33 05:03 »

I designed and built 4 LED module with 10 channel PWM using CAT4101
http://www.onsemi.com/pub_link/Collateral/CAT4101-D.PDF
I was driving the LEDs with 700ma max so no heatsink required just a larger heat pad.
The last image all 30 led running at 50% iPhone camera couldn't take it properly.
 
This picture are from the fits prototype using PCA9685 i2c






Logged
Old_but_Alive
V.I.P
Active Member
*****
Offline Offline

Posts: 211

Thank You
-Given: 154
-Receive: 56


« Reply #4 on: September 15, 2013, 05:39:38 05:39 »

the CAT4101 is a linear constant current device, so not efficient, and requires heatsink.

most LED driver IC's are switch mode devices, so have >80% efficiency, and thus low power dissipation.

I use the LT3476
Logged
Catcatcat
Active Member
***
 Warned
Offline Offline

Posts: 117

Thank You
-Given: 89
-Receive: 258



WWW
« Reply #5 on: September 15, 2013, 02:32:04 14:32 »

CAT4101 be correctly connected, there is no need for the radiator. I would recommend not to use the PWM controller and the standard PWM drivers who use inconsistent counters, and the output drivers install a powerful current...
Logged
chandra2sekhar2000
Active Member
***
Offline Offline

Posts: 121

Thank You
-Given: 22
-Receive: 17


« Reply #6 on: September 15, 2013, 02:47:00 14:47 »

why cant u try power psoc Controllers
Logged
Luigo
V.I.P
Newbie
*****
Offline Offline

Posts: 10

Thank You
-Given: 9
-Receive: 2


« Reply #7 on: September 21, 2013, 07:25:35 19:25 »

This is an exelent project http://picprojects.org.uk/projects/bigmosfetrgb/index.htm
You can find a lot of good information http://picprojects.org.uk/projects/picprojects.htm
Logged
Pages: [1]
Print
Jump to:  


DISCLAIMER
WE DONT HOST ANY ILLEGAL FILES ON THE SERVER
USE CONTACT US TO REPORT ILLEGAL FILES
ADMINISTRATORS CANNOT BE HELD RESPONSIBLE FOR USERS POSTS AND LINKS

... Copyright 2003-2999 Sonsivri.to ...
Powered by SMF 1.1.18 | SMF © 2006-2009, Simple Machines LLC | HarzeM Dilber MC