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R_Mc
01/31/2015, 04:47 PM
Phoning the veterans on this one.

I'm planning on running either 2 or 4 drivers for the following configuration:

SPECIFICATIONS:
LED Configuration

Channel 1:
Cree XPE Royal Blue 5pcs
DC Forward Voltage (VF): 15V
DC Forward Current (IF): 350mA ~ 1000mA

Channel 2:
Cree XPE Red 3pcs
Epileds Cyan 2pcs
DC Forward Voltage (VF): 12V
DC Forward Current (IF): 350mA ~ 600mA

Channel 3:
XPE Cool White 6500K 5pcs
DC Forward Voltage (VF): 15V
DC Forward Current (IF): 350mA ~ 1000mA

Channel 4:
Cree XPE Blue 3pcs
Epileds 420nm Purple 2pcs
DC Forward Voltage (VF): 13V ~ 14V
DC Forward Current (IF): 350mA ~ 600mA

To drive everything at the lowest pricepoint I think i'd have to use one 600ma for channels 2 and 4, then a 1a driver for channels 1 and 3. The downside is control over color mixing.

I already have a 15-24V dc power source (70W), so I only need DC-DC drivers.

looking at this series right now: http://www.digikey.com/product-detail/en/RCD-24-0.60%2FW%2FX1/RCD-24-0.60%2FW%2FX1-ND/2303643 but they're $14/20 per driver

Anyone know a cheap DC-DC solution for driving each channel individually?

Thanks :wave:

O2Surplus
01/31/2015, 05:22 PM
Use Meanwell LDD-H drivers. They're only 7-8 bucks each and available from most of the online DIY led sellers. They're a pretty popular driver choice around here. Rapid's got 'em-http://www.rapidled.com/dimmable-drivers/

zachts
02/01/2015, 12:32 AM
Cheaper from powergate as long as you're ordering more than just 4......shipping is a little high...

theatrus
02/01/2015, 01:18 AM
All in one solution? Meanwell LDD.

Custom PCB? You can do cheaper in quantity. But for a one-off build probably not.

R_Mc
02/01/2015, 08:10 AM
Thanks - these look perfect. I want to start with simple analog dimming. Will have to look up an addon circuit for that.

zachts
02/01/2015, 10:47 AM
Thanks - these look perfect. I want to start with simple analog dimming. Will have to look up an addon circuit for that.

there are several floating around google "10 volt to pwm converter" works with a pot and a 10v power supply (some don't need the extra power supply)

or

make your own using a cheap arduino pro mini (or any arduino for that matter) and pots to do the conversion and dimming (actually all the boards use an arduino chip anyhow) a very basic sketch (attached) would do the conversion of the pot setting and output pwm to the drivers. you could convert it to a proper controller latter via revised sketch and adding an RTC, lcd screen, and buttons and such.

O2Surplus
02/01/2015, 02:45 PM
there are several floating around google "10 volt to pwm converter" works with a pot and a 10v power supply (some don't need the extra power supply)

or

make your own using a cheap arduino pro mini (or any arduino for that matter) and pots to do the conversion and dimming (actually all the boards use an arduino chip anyhow) a very basic sketch (attached) would do the conversion of the pot setting and output pwm to the drivers. you could convert it to a proper controller latter via revised sketch and adding an RTC, lcd screen, and buttons and such.

Here's the simple dimmer that I build. 4 independent channels of 8bit dimming with just the twist of a knob.

http://i861.photobucket.com/albums/ab172/kovawa/8upLDD-H_with_Dual_SCW003_zps2fda3cf2.jpg

perkint
02/02/2015, 02:38 AM
You say you're thinking of 2 or 4 drivers.

If your PSU only goes to 24V, you need 4 drivers or to run the strings in parallel. 4 drivers is a much better bet...

Tim

SeargentSlice
02/02/2015, 05:47 AM
I cant link source for some reason ill try pm

R_Mc
02/02/2015, 03:42 PM
I'm thinking I can just use 4 of these for PWM on the cheap? would be <$15 to control all 4 channels. Cant find anything close to this out there.

http://www.ebay.com/itm/2A-Motor-Speed-Switch-Controller-PWM-1803BK-self-recovery-Fuse-DC-1-8V-3V-5V-6V-/201199388878?pt=LH_DefaultDomain_0&hash=item2ed86b08ce

If there's a better part at a similar price let me know. I'm not exactly sure how the output is controlled or...what it is with this item. Also seems totally overkill at 30W. There must be a cheaper/simpler pure PWM (no drive) solution.

R_Mc
02/02/2015, 03:47 PM
Wait a minute:

http://www.ebay.com/itm/3-5-PC-Computer-Case-CPU-HDD-4-Channel-Fan-LED-Speed-Controller-Control-Cooling-/281585386141?pt=LH_DefaultDomain_0&hash=item418fcc029d

This would be great! Is it a PWM controller? It's my understanding that that is how fan speed is modulated.

oreo57
02/02/2015, 03:50 PM
I'm thinking I can just use 4 of these for PWM on the cheap? would be <$15 to control all 4 channels. Cant find anything close to this out there.

http://www.ebay.com/itm/2A-Motor-Speed-Switch-Controller-PWM-1803BK-self-recovery-Fuse-DC-1-8V-3V-5V-6V-/201199388878?pt=LH_DefaultDomain_0&hash=item2ed86b08ce

If there's a better part at a similar price let me know. I'm not exactly sure how the output is controlled or...what it is with this item. Also seems totally overkill at 30W. There must be a cheaper/simpler pure PWM (no drive) solution.
Not sure why nobody uses or mentions them but Buck pucks come like this:
http://www.ledsupply.com/images/products/03023-d-e-1000p.jpg

Generally they are more expensive than Meanwells..
Or add a $50 Typhon from Steves for a 4 channel PWM dimmer...
But back to your orig problem..PWM signal based on a 555 timing chip..
http://www.ebay.com/itm/like/321143973713?lpid=82&chn=ps
Module Parameters:

Module Size: 45 * 24 * 25mm

Main Chip: NE555
Working Voltage: DC 4~16V
Working current: no higher than 10mA
Maximum Output Current: 225mA
Output Frequency: 10Khz ( buyer can change frequency by changing capacitor)
Output duty ratio adjustable 0~100%

add a 5V PS and you "should" be good to go.. (have others verify this though)
Problem is it 4 are 1/2 the price of a 4 channel Typhon.. and all "manual"...........

http://shop.stevesleds.com/Typhon-Typhoon-LED-Controller-8794102479.htm

asdfghp
02/02/2015, 04:05 PM
Hi,
I've had good luck with various components from stevesleds.com
Also Led group buy.com
Color mixing is done with an AB PLC and Maple Systems HMI via 0-10v output going thru a PWM converter. Dial up what ever color or mood suits your fancy. Can make some pretty sweet light shows, too!
J

R_Mc
02/02/2015, 04:24 PM
Looks like the only reason I may not be able to use the fan speed controller is the PWM frequency... Anyone have a datasheet for the product linked? Looking at similar I'm seeing very high speed PWM for 4 pin fans and relatively low speed (30hz) for 3 pin?

I assume that these fan speed controllers are 555 based - if so It's likely that I could change the timing with a capacitor swap, right?

Spec for LDD pwm input is 100hz-1khz

oreo57
02/02/2015, 04:40 PM
Wait a minute:

http://www.ebay.com/itm/3-5-PC-Computer-Case-CPU-HDD-4-Channel-Fan-LED-Speed-Controller-Control-Cooling-/281585386141?pt=LH_DefaultDomain_0&hash=item418fcc029d

This would be great! Is it a PWM controller? It's my understanding that that is how fan speed is modulated.
no...
Maximum Adjustable Range: 5-12V
http://www.newegg.com/Product/Product.aspx?Item=9SIA3XT1R66878
Input voltage :12V
Output voltage:5V to 12V

R_Mc
02/02/2015, 04:54 PM
Not sure what you mean - the specs I'm seeing for fans: http://www.sanyo-denki.com/currentcooling/cooling_fans/onlinecatalog/index.pdf

indicate that they're controlled with a similar off @ 0-.4VDC on @ 2~5VDC like the meanwell. I believe that the 5~12V indicates the "high" voltage on the output, not the low-high.

\The real question is just the PWM frequency which looks to be 25KHZ based on the same datasheet above - 25x faster than the max spec provided by meanwell... hrmm...

Has anyone tried controlling with a much faster PWM frequency than specced? if so - how did the driver output behave?

oreo57
02/02/2015, 04:58 PM
Not sure what you mean - the specs I'm seeing for fans: http://www.sanyo-denki.com/currentcooling/cooling_fans/onlinecatalog/index.pdf

indicate that they're controlled with a similar off @ 0-.4VDC on @ 2~5VDC like the meanwell. I believe that the 5~12V indicates the "high" voltage on the output, not the low-high.



you asked about a "pot" controller.. Doesn't matter what the fan wants..
That controller is simple voltage limiter via resistance AFAICT...

you know, I have to ask this.. Why are you trying to skimp on the very thing that makes LED's so desirable?.. dimming, programming and control.. Makes no sense..
The Typhon is just a pre-programmed aduino w/ "shields" like a clock chip ect.. Not pushing it per se.. just a bit baffled..;)

If you get PWM controlled fans you are still back at square one...

R_Mc
02/02/2015, 05:03 PM
Man that wouldn't work... you're absolutely right. I guess I'm looking for a PWM based fan speed controller - which also seem to be out there and look almost identical...

http://www.frozencpu.com/products/15133/bus-307/Logisys_6-Channel_PWM_and_3-Pin_Fan_Controller_FP600BK_-_36W_per_Channel.html?gclid=Cj0KEQiA3bymBRC19IrD7O_NrYsBEiQAb2dpAw46h0lx25WmnJPgY4-L5o5ncBir5tTFGD0Msst4-cAaAoss8P8HAQ

oreo57
02/02/2015, 05:26 PM
Man that wouldn't work... you're absolutely right. I guess I'm looking for a PWM based fan speed controller - which also seem to be out there and look almost identical...

http://www.frozencpu.com/products/15133/bus-307/Logisys_6-Channel_PWM_and_3-Pin_Fan_Controller_FP600BK_-_36W_per_Channel.html?gclid=Cj0KEQiA3bymBRC19IrD7O_NrYsBEiQAb2dpAw46h0lx25WmnJPgY4-L5o5ncBir5tTFGD0Msst4-cAaAoss8P8HAQ

worth a read:
http://www.swiftech.com/pwmcontrollers.aspx
http://www.overclockers.com/pwm-fan-controller/

Actually it "is" a bit more complicated than I orig. assumed..
But still leads me back to this:
http://www.ebay.com/itm/like/321143973713?lpid=82&chn=ps

zachts
02/02/2015, 06:31 PM
I'm thinking I can just use 4 of these for PWM on the cheap? would be <$15 to control all 4 channels. Cant find anything close to this out there.

http://www.ebay.com/itm/2A-Motor-Speed-Switch-Controller-PWM-1803BK-self-recovery-Fuse-DC-1-8V-3V-5V-6V-/201199388878?pt=LH_DefaultDomain_0&hash=item2ed86b08ce

If there's a better part at a similar price let me know. I'm not exactly sure how the output is controlled or...what it is with this item. Also seems totally overkill at 30W. There must be a cheaper/simpler pure PWM (no drive) solution.

arduino pro mini ~$5
4 pots either 5kohm or 10kom, dirt cheap ($1.50 from steves leds also all over the net)
.....plus, you then have the flexibility to turn it into a controller later.......
total cost ~$9, (but then you have some shipping or just get the leds from steves also....)
Just my two cents.

zachts
02/02/2015, 06:34 PM
you asked about a "pot" controller.. Doesn't matter what the fan wants..
That controller is simple voltage limiter via resistance AFAICT...

you know, I have to ask this.. Why are you trying to skimp on the very thing that makes LED's so desirable?.. dimming, programming and control.. Makes no sense..
The Typhon is just a pre-programmed aduino w/ "shields" like a clock chip ect.. Not pushing it per se.. just a bit baffled..;)

If you get PWM controlled fans you are still back at square one...

Better than the typhon is the storm controller, about $10 more but way way better IMHO!

oreo57
02/02/2015, 06:57 PM
Better than the typhon is the storm controller, about $10 more but way way better IMHO!

Every time I look at that one .. I lean to the Storm X.......Currently the Storm is $15 more.. Storm X about..$50 more..

zachts
02/02/2015, 08:36 PM
Every time I look at that one .. I lean to the Storm X.......Currently the Storm is $15 more.. Storm X about..$50 more..

LOL! how many really need more than 6 channels though?.......well other than me :lolspin:

perkint
02/03/2015, 07:37 AM
arduino pro mini ~$5
4 pots either 5kohm or 10kom, dirt cheap ($1.50 from steves leds also all over the net)
.....plus, you then have the flexibility to turn it into a controller later.......
total cost ~$9, (but then you have some shipping or just get the leds from steves also....)
Just my two cents.
This!!!

As if it was designed for the LDDs and can easily update from manual dimming by adding a $1 RTC and have it control the LEDs automatically to add sunrise, sunset, moonlights, etc.

Tim

R_Mc
02/03/2015, 07:59 AM
I'll have to read up on the arduino option. Any links to more detailed instruction would be very helpful.

but at the very least - it looks like I'll at least need a FTDI breakout board, breakaway headers:
https://www.sparkfun.com/products/9873 $15
https://www.sparkfun.com/products/116 $1.50

Which brings me back up to the mid $20's and about the same cost as just buying 4 pwm controllers again.

R_Mc
02/03/2015, 08:20 AM
Does the arduino come with any code on it? Would it have to be modified?

I assume if code needs to be written it would just be to take a voltage input on the analog pins controlled by a pot and translate it to the appropriate duty cycle...but I have never programmed one of these before.

oreo57
02/03/2015, 09:03 AM
Does the arduino come with any code on it? Would it have to be modified?

I assume if code needs to be written it would just be to take a voltage input on the analog pins controlled by a pot and translate it to the appropriate duty cycle...but I have never programmed one of these before.

Well it is a bit more complicated .. ;)
https://www.boostled.com/Articles.asp?ID=250

perkint
02/03/2015, 12:34 PM
If all you want is manual dimming, it is as simple as setting the PWM in proportion to the input voltage from the pot, yeah. In fact, you could probably combine reading from the input, calculating the PWM value and setting it into one line per channel (using the map function).

And no - you don't need the FTDI with the nano - for less than $5 you can get one with mini USB on board :)

Tim

zachts
02/03/2015, 12:48 PM
I'll have to read up on the arduino option. Any links to more detailed instruction would be very helpful.

but at the very least - it looks like I'll at least need a FTDI breakout board, breakaway headers:
https://www.sparkfun.com/products/9873 $15
https://www.sparkfun.com/products/116 $1.50

Which brings me back up to the mid $20's and about the same cost as just buying 4 pwm controllers again.

arduino nano or uno can be had for under ~$8 on ebay and have the usb FTDI built in. Just got some uno's in the mail today that were only $4.50, but they came on the slow boat from china so took a month to get them.......

zachts
02/03/2015, 12:51 PM
Does the arduino come with any code on it? Would it have to be modified?

I assume if code needs to be written it would just be to take a voltage input on the analog pins controlled by a pot and translate it to the appropriate duty cycle...but I have never programmed one of these before.

I posted the code you need for manual dimming on the first page in a zip file. all you do is plug the arduino into your computer, open the arduino IDE (program you download for free) and upload the code. then just wire things up and your done in under 10min if you solder fast :)

perkint
02/03/2015, 12:53 PM
Not sure why, but these don't seem to come up on ebay.com (but do on ebay.co.uk):
http://www.ebay.co.uk/itm/Mini-USB-Nano-V3-0-ATmega328P-5V-16M-Micro-controller-Board-For-Arduino-JUST-/151542865093?pt=UK_BOI_Electrical_Components_Supplies_ET&hash=item2348a89cc5

Tim

R_Mc
02/03/2015, 01:05 PM
Thanks Zach - missed that & reading through it now.

So I will have to use a 5V power supply over the pots... I feel like I also need to current limit this somehow - when I dim the lights down all the way I will get 5V over...maybe 10 ohms or 500ma which seems pretty high...

Should I add a 1k ohm resistor in series (on the high side) with each of pots to ensure that the current will not exceed 50ma?

Then change the code
eg from: analogWrite(3, read1/4);
eg to: analogWrite(3, (read1 +93)/4);

The +93 being that the analog input will now be between 0V and ~4.545V which equates to an input value of 0 to (4.545*1023)/5=929.907
1023 - 929.907 = 93.093

zachts
02/03/2015, 05:57 PM
Thanks Zach - missed that & reading through it now.

So I will have to use a 5V power supply over the pots... I feel like I also need to current limit this somehow - when I dim the lights down all the way I will get 5V over...maybe 10 ohms or 500ma which seems pretty high...

Should I add a 1k ohm resistor in series (on the high side) with each of pots to ensure that the current will not exceed 50ma?

Then change the code
eg from: analogWrite(3, read1/4);
eg to: analogWrite(3, (read1 +93)/4);

The +93 being that the analog input will now be between 0V and ~4.545V which equates to an input value of 0 to (4.545*1023)/5=929.907
1023 - 929.907 = 93.093

Most All arduino boards will have an onboard 5v source available so you shouldn't need an extra supply.

ASFAIK you only need limiting resistors when using the arduino pins as outputs. In this case they are configured as input and only reading voltage so not much current will be flowing. if using voltage from a tiny on board regulator like on the pro mini that I use for lots of stuff the limiting resistor might not be bad to help protect the regulator in event of an accidental short (then a gain most regulators have internal over current and over temp protection built in)

Compensating for the resistor if you used it isn't really necessary in this case. You only loose a few points of resolution but the output pwm is still going to be 0-255 or 0-100% brightness from the LEDs. the code you edited would result in not being able to hit 0% brightness and would cause the signal to roll back over to zero and start dimming back up as you turned the pot up to what would be near 100% (if you try to write a value above 255 it rolls over unless you add a line of code that limits this by saying any value over 255 = 255 etc.

R_Mc
02/03/2015, 06:24 PM
Thanks you're totally right I had a mind melt and forgot that the resistance would always be 10k across the pot for the 5v pin.