8Ch RGB Strip controller

[Matt_Edwards]

This year I am converting my leaping arches to strip RGB LEDs.
I want to keep 8 sections per Arch and obviously there are 3 colours per section.
So this is what I have come up with.
The work is heavily based on RPMs 16ch DC DMX controller.

Most LED Strip are either 12 or 24 volt (12 is very popular).

As can be seen, the PCB is 4x4. The Fets are IRLL014N (Vdds =55v, Ron = 0.14 Id= 2A)
I opted not to fit a board mounted fuse, so I will be using a chassis mount on the case.
The design is still draft as I have really chosen the case yet. Jaycar CAT. NO. HB6248 (http://jaycar.com.au/productView.asp?ID=HB6248&CATID=5&form=CAT&SUBCATID=720) - Poly Carbonate 171 x 121 x 55 is a possibility, although I would prefer one about 125x125x55. What ever they end up being they will be permanently mounted on one end of the arch and will have DMX in/out and power connectors so they don't need to be easily opened.

I haven't decided if I will put isolated DMX I/P yet.

Comments are welcome. I don't intend to order prototype boards for a month or so.

[RPM]

Matt, I am working on something similar at the moment using SMD 5050 RGB LED's.
It's based on the Color Stick design by Mike n1ist, where there will be a small PCB inserted into a length of translucent "PEX" or similar type of tubing. Here's a link to the color stick thread http://doityourselfchristmas.com/forums/showthread.php?11644-Color-Stick

I am current using Mike's Color Stick PCB's in my prototype, but I plan on designing my own PCB out of thinner material so it will semi-flexible, that will be longer than the .75x13" color stick board, and I've already got my own version of firmware ready for it.
The firmware is currently 24 channels for 8 RGB LED's, but can be expanded for up to 96 channels for 32 RGB LED's, using an Atmega48.

The basic idea is to make the PCB self contained and small enough to fit into the tubes that will only require a 12vdc power source and a DMX signal. This will require the design to be done in SMD, as I don't think it can be done with DIP sized parts.

[Matt_Edwards]

RPM,
Mikes ColorStik was also a consideration. The TLC5916 LED Drivers sink capability just was not high enough, I need 200 to 300 mA drive. also I may use 24v strip light, Vmax for the TLC5916 is 20v.

(BTW, actually the colorstick is the reason for me using 0603 resistors for the fet gates)
Cheers

[RPM]

RPM,
Mikes ColorStik was also a consideration. The TLC5916 LED Drivers sink capability just was not high enough, I need 200 to 300 mA drive. also I may use 24v strip light, Vmax for the TLC5916 is 20v.

(BTW, actually the colorstick is the reason for me using 0603 resistors for the fet gates)
Cheers

Have you looked at the TPIC6A595? 350mA drive @ 50V.
What LED's are you going to use with your board?

[Matt_Edwards]

Ah I remember you mentioning this device early. They may just be suitable and will definitely save on space.

The on-board LEDs, Act & Err, are 1206 size. They may change to 0805 as I have some on the way.

The LEDs for the arches are RGB flexible waterproof strips (http://www.aliexpress.com/fm-store/701799/209843764-361563493/5m-5050-RGB-waterproof-led-flexible-strip-IP65-with-controller-44key-IR-and-power-adaptor.html), they use 5050 size LEDs.

[Mactayl]

I think you have a good plan for the 8 Channel RGB LED Strip arches, I would like to build some myself, also the 4x4 is a good compact size. very well done. ;)

[RPM]

Ah I remember you mentioning this device early. They may just be suitable and will definitely save on space.

That's what I was thinking... either way, I like the layout of your board. Nice and compact.

Also, the Fairchild FQT13N06LTF is another FET that can be used

http://www.mouser.com/Search/ProductDetail.aspx?R=FQT13N06LTFvirtualkey51210000 virtualkey512-FQT13N06LTF
It's just the SMD version of the FET I use in my 8 channel DC board.



The on-board LEDs, Act & Err, are 1206 size. They may change to 0805 as I have some on the way.

The LEDs for the arches are RGB flexible waterproof strips (http://www.aliexpress.com/fm-store/701799/209843764-361563493/5m-5050-RGB-waterproof-led-flexible-strip-IP65-with-controller-44key-IR-and-power-adaptor.html), they use 5050 size LEDs.

I was on the fence with this one too. The LED strips are another design I was thinking of, just a bit more wiring than I want to do. I'm interested in seeing one built up ;)

[Matt_Edwards]

Here's some a revelation,
Based on 100 boards the 300x TPIC6A595 drivers would be $330 dearer than 2400x FQT13N06LTFFets and 300x HC595 (SOIC-16 case)

Making it smaller comes at a cost.

anyway finalised layout a bit more tonight.

[Matt_Edwards]

Made a few changes - added a basic SMPS supply to improve overall power efficiency.
Now I need to decide if I should split the Power input connector in to 2 and place them near R25 and R24. The current of the 12v strip is pretty high.

http://baulkolites.com/wp/wp-content/uploads/2011/02/8ChRGB-PCB-RevB.png

Can't wait for Chinese New Year to finish so I can order some prototypes.

[RPM]

Matt,

A couple of areas I see that may be of concern... the VIAS just next to C1 and C8 are pretty close and may have problems with solder bridging if hand soldered.
Also maybe change the FET designators from V3-V26 to V1-V24 to make it correspond better to the output terminals.

The SMPS is a good change, but I have found that there is a really bad shortage of these regulators from Mouser.
Maybe use a linear regulator with an input current limiting resistor with the value selected depending on voltage range? I have considered this on my designs because of the part supply problems with the SMPS regulator.

Otherwise, it looks like it's coming along pretty well.

Robert



Made a few changes - added a basic SMPS supply to improve overall power efficiency.
Now I need to decide if I should split the Power input connector in to 2 and place them near R25 and R24. The current of the 12v strip is pretty high.


Can't wait for Chinese New Year to finish so I can order some prototypes.

[Matt_Edwards]

Robert,
Thanks for your input. The via near C1 is connected to the pad it might short out. C8 is an issue, well spotted. I will correct. It would be cool to have the solder resist cover all the vias to there is not wave solder can bridge. It also makes it harder to mods.

As for the SMPS, I understand the issue, so I may add extra pads so you can fit either or. I still have 100x LM2574-5 units so am pretty keen to use them.

[RPM]

Robert,
Thanks for your input. The via near C1 is connected to the pad it might short out. C8 is an issue, well spotted. I will correct. It would be cool to have the solder resist cover all the vias to there is not wave solder can bridge. It also makes it harder to mods.

Now I see that one side of C1 is connected to the same plane as the via... C8 can be a potential problem though.


As for the SMPS, I understand the issue, so I may add extra pads so you can fit either or. I still have 100x LM2574-5 units so am pretty keen to use them.

I also have a few hundred of the LM2574-5's, so it's not an issue with me. I was thinking more if you were to co-op the boards then a linear regulator may be a better choice for availability.

[ackcsaba]

Hello Matt!

I built your rgb controller, but I cannot found the program for ATTiny2313. Where can I found it?? If nowhere, please send me.

Thanx
Csaba

[Matt_Edwards]

Hello Matt!

I built your rgb controller, but I cannot found the program for ATTiny2313. Where can I found it?? If nowhere, please send me.

Thanx
Csaba

Csaba,
I won't release the final Schematics and code until I have tested the prototypes.
I intend to order protos this week end.

[Matt_Edwards]

Prototypes were ordered last night.
At RPM's suggestion, the output connectors were renamed X1 to X8 and a Linear Regulator was added as an option. The layout is such that you will either fit the 78L05 or the LM2574, but can't fit both.
The size is still 100x100 mm.

[Matt_Edwards]

I just finished building the first prototype.
http://baulkolites.com/wp/wp-content/uploads/2011/02/005.jpg

Cheers

[Mactayl]

Very impressive Matt... what is the current capability per channel and what size is the PCB

[dirknerkle]

The board is too... too... uhhhh... RED, yah, that's it! It's too red. Looks very tidy and compact (about 4" square?).

Really nice work. Can't wait to hear how it performs for you!

-dave

[tweist]

Excellent work. You must have really steady hands to be able to solder that small of parts.
Looks great, and I can't wait to see some video on how it works.

[Matt_Edwards]

Design spec is 1.1 to 1.5Amps per channel. I wanted a 5m RGB (12v type) strip per group, or 2x5m (24v type) strips per group.

I an yet to test the voltage drop and temp rise of the main track at full load.

Size is 101 x 99mm.
My first use will be 8x 500mm sections for 12v RGB strip for my Leaping Arches.

[keebler]

very impressive matt!
will you be making these available sometime?

keep up the great work :)

[Matt_Edwards]

YES. nor sure in what format yet, probably PCBs and code here, with an option to purchase fully assembled and semi made kits, ie all SMT complete and pre-programmed from my site.

[keebler]

excellent. please keep us informed

[dmcole]

YES. nor sure in what format yet, probably PCBs and code here, with an option to purchase fully assembled and semi made kits, ie all SMT complete and pre-programmed from my site.

This puts an interesting spin on my arch project (which never got off the ground last year). I looked at the strips you plan to use at Aliexpress ... how do you plan to get them onto (into?) arches?

\dmc

[tweist]

Any chance of getting a bill of materials soon?

[Matt_Edwards]

Currently the component costs are sitting around $16 per controller (in 100 off qty)

[Matt_Edwards]

They Live.
I RX'd the RGB Strips this week. So connecting full 5m strips at 12 Volt and all is sweet.
So far after 36hours burn in, there is a .2v drop from the TB to the first LED strip on the common +ve track. I can live with that. Hopefully my mate will drop off his IR thermometer and I will measure the temp rise.
http://baulkolites.com/wp/wp-content/uploads/2011/02/8ChRGB-Purple-test-226x300.png http://baulkolites.com/wp/wp-content/uploads/2011/02/8ChRGB-Red-test-228x300.png

Now to build the Arches.

[dirknerkle]

Awwwww, geez.... photos like that.... now you're just messin' with our minds!!!




(Looks great, BTW...)

[Mactayl]

Looks really good Matt
Very nice job.

[erm213]

OK, I assume that the lights on the strip are not individually addressable? Do they even make those kind of strips.

Erik

[mlkren]

You are correct, these are not addressable individually. Thus a dumb string and not a smart string.:)

[Matt_Edwards]

That is rights, this controller is intended 3 channel RGB strip (http://www.aliexpress.com/fm-store/701799/209843764-308758789/5m-one-roll-5050-SMD-30LEDs-m-led-strip-non-waterproof-RGB-color-.html).

[Matt_Edwards]

OK made timeto progress the arches again.
http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch1.jpg

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch2.jpg

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch3.jpg

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch4.jpg

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch5.jpg

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch6.jpg

[JerryPlak]

Matt, what type of cable are you using and wear did you find this cable

[Matt_Edwards]

Matt, what type of cable are you using and wear did you find this cable

7/0.20 Alarm wire. I source from Altronincs Cat # WB1590. they also have 4.5 mm rubber grommet (CAt # H1462) that are a nice fit for the cable entry.

[erm213]

Looking good, when do we get some shots of them running? :)

Erik

[mschell]

I agree, pictures of them running would be good. I'm still trying to understand how you are going to bend this and where the strip points....

[Matt_Edwards]

The strip in placed on the top pf the arch.
Bending is very easy as I only glue one end of each strip ( the cable entry end) to the conduit. the cable run do the side ot the curve

http://baulkolites.com/wp/wp-content/gallery/leaping-arches/arch6-notation.jpg

The remander of the strip is free to slip as the arch bends. When I put the arch in place I need to adjust the strips into their final position.
I used the same method for rope light arches. so I know it works.

[mschell]

Understand now how you put it on. Only issue I see is how much light shows towards the "front" of the arch. Rope light shines in all directions, but these LED strips seem to more directional...

I'm planning a single color arch, and thinking of putting the LED strip in small translucent pipe to make it look "bigger".

[Matt_Edwards]

Another solution I have toyed with is fixing the LED Strip to a Fiber glass spar. this would then be placed in a PVC tube. I purchased some non-waterproof strips to try.