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General Discussion => General Electronics => Topic started by: dougal on June 14, 2013, 08:02:32 am

Title: Individually addressable RGB LED comparison?
Post by: dougal on June 14, 2013, 08:02:32 am
So I know there's WS2801, WS2811, and LDP8806 controllers for LED strips. What others should we be aware of?


Can someone point us to (or write up) a breakdown comparison of the features/limitations of the various options?

Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on June 15, 2013, 07:32:49 pm
From what I understand, WS2801 and LPD8806 are both SPI-based chipsets. Both do 8-bit PWM and have RGB channels. Both come as separate chips which are connected to any sort of RGB LED, available as fairy-light strings or as strips. LPD8806 seems to be patent encumbered and less available for purchase than the WS2801 stuff. LPD8806 are very poorly documented - adafruit managed to reverse engineer enough of how they work to make an arduino library. The LPD* chips generally also do not freerun - this means your microcontroller needs a background process (timer or watchdog interrupt) pausing your program and sending out clock signals to the LEDs even when you aren't outputting colours. This clock signal runs their PWM. If you make it too fast, the colours will start to be reproduced less accurately - if you make it too slow, they will look flickery and might be an epilepsy risk.


For those reasons, I recommend you do not use LPD8806. WS2801 is a similar SPI device with a seperate chip. You can hook it up to a raspberry pi, a serial or parallel port on a computer, a digispark, littlewire, and arduino - pretty much anything capable of digitally writing to two wires. The WS2801 runs it's PWM off an internal clock, so you can set it and forget it - they'll hold their colour without needing your program to be interrupted thousands of times every second.


The WS2811/WS2812 is really neat! The WS2811 is a chip, like the ws2801, but instead of SPI it uses a purely timing-based serial protocol. They can be driven by an arduino or digispark running at 8 or 16 megahertz, they hold their colour (set and forget) just like the ws2801, and are basically the same, but you only need a single data wire instead of two, making them very appealing for use with digispark.


The WS2812 is the WS2811 chip die embedded in to a 5050-style LED, so you have an all in one addressable chainable LED module. You can buy these on 60-led per meter strips on aliexpress or from adafruit. All ws2812 LED modules run in the 800khz protocol, not the 400khz protocol available on some ws2811 devices. This means they run at twice the speed, allowing your program to communciate with them faster, so each time you send an update to your LEDs your program will spend less time doing it, and get back to your colour calculation code quicker - this potentially means a higher framerate. We also have out of the box support for 800khz ws2811 and ws2812 lights built in to the beta version of LittleWire 1.2 and included in the littlewire ruby library and c library. This means you can use a digispark to control ws2811 and ws2812 LEDs from a computer via a digispark without needing to write any arduino code or figure out how to interface with the digispark from your program - you just pass an array of colours to the littlewire libraries and it handles it all for you.


Another key difference is because of the strict timing requirements of ws2811/ws2812k, you need to precompute the colours for all of your LEDs and then use a function which outputs them from an array. You can't do streaming output, where you compute a single colour, send it out, compute the next one, etc... You can stream output with ws2801 and to some extent lpd8806 devices. This can be relevent to digispark and arduino projects because digispark only has 512 bytes of ram, and each LED takes 3-4 bytes of that memory depending on the library you use. This means you are practically limited to buffering about 100 WS2811/WS2812 LEDs in a digispark's memory. On the newer arduinos you can do a few hundred more. The Teensy 3.0 can do a bunch more still.


This limitation isn't as bad as you might think, because you can have multiple parallel strips! You fill your buffer with data for one strip and output it, then fill it with colours for a different group of LEDs and output it to a different pin! With this technique you can have roughly (100 * number of free pins) - if you have nothing else connected to a digispark it can control 600 LEDs!


In summary, I would recommend using ws2812/ws2811 (800khz) for all projects except where you want to drive LEDs from an SPI port, like that of the raspberry pi. For raspberry pi driving LEDs directly, use ws2801. Only use LPD* lights when you have to for compatibility with something else.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 17, 2013, 06:35:10 am
Great info, Bluebie, exactly what I was hoping for!


I've got a 1m strip, a 5m strip, and a string of 50 12mm lights, all WS2811-based, on the way from eBay auctions. The first one should hopefully arrive today, and the others next week. I just wanted to make sure there wasn't some other type that would be better to focus on.


I'll be downloading your drivers as soon as I get a chance.  :)
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 19, 2013, 08:56:08 am
I just scored a lot of 100 individual ws2812 modules on eBay for $25. w00t!


http://www.ebay.com/itm/171058502069?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649


That's the best price/quantity deal I've seen, short of buying lots of 500 or more.

Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on June 27, 2013, 02:43:24 am
You are sure those are WS8212 with the integrated rgb led ? I know the ebay pictures seems to show that, but they are described as WS8211...

Anyway, thanks for sharing. I think I might get a pack too...
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 27, 2013, 01:49:58 pm
Going by the pictures, and this blog entry (http://propaneandelectrons.com/blog/the-difference-between-ws2811-and-ws2812), it looks like WS2812 modules, to me.


I'm guessing that they used WS2811 in the description because more people are searching on that keyword? (though you'd think they'd put both terms in for maximum coverage...)


I dunno. I'm just looking forward to receiving them. :)



Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 27, 2013, 02:10:50 pm
Over on AliExpress, it looks like you can get them even cheaper *if* you buy multiple 100-piece lots. The lots are $14 each, but they add $20 shipping. However, it looks like the shipping stays the same even for a large number of lots:


http://www.aliexpress.com/item/5050-SMD-RGB-LED-with-built-in-WS2811-IC/656558600.html (http://www.aliexpress.com/item/5050-SMD-RGB-LED-with-built-in-WS2811-IC/656558600.html)

Title: Re: Individually addressable RGB LED comparison?
Post by: digistump on June 27, 2013, 04:05:51 pm
What are you folks using these for - generally one or many at a time? I'm wondering what form a breakout/shield for these should take or if we should just carry them individually/in 10 and 100 packs? I imagine we could offer them for $25 for $100 (or less) without the china shipping wait times
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on June 28, 2013, 01:34:32 am
My plan is to make a clock out of those. Take 60 of them disposed in a circle shape, light up 3 of those at a time for hours, minutes and seconds, with different colours (and mixing when they overlap) for each unit.

Not something that would fit on a spark shield, but a spark should be enough to drive it.


I think people would probably make customs forms or shapes out of many those. If you only use a single you don't need the chaining capability, and if you only want a straight line you can buy premade strips.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 28, 2013, 07:27:03 am
I don't have any specific plans for them yet. But I was on an LED strip buying spree, and getting a big lot of individual elements seemed like a good idea at the time. :)


The pre-built LED strips are great, but if you don't want a linear layout, or if you need to vary the spacing, you have to cut them apart and wire them anyhow.


They're small (5mm square -- less than 1/4" for us Imperialists), so they'd be good for all sorts of projects where you want to use a lot of little blinkenlights -- more than you could control with charlieplexing. You could make a 10x10 matrix in right around 2" of space, if you squeeze them tight. They'd be good for making your own wearables, like the AdaFruit Flora NeoPixels.


What I'm starting to wonder is if there might be any value in making some sort of I2C interface for WS2811 hardware? You could offload the timing and RAM requirements to a large degree. And it wouldn't need to be DigiSpark-specific.



Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on July 01, 2013, 09:14:22 pm
I don't know if this will interest anyone, but I started working on a browser-based JavaScript simulation of LED strips. You can view it on CodePen:


http://codepen.io/dougalcampbell/pen/fnjFu


It is currently emulating the 'chasers' code from Danny Havenith's WS2811 AVR library:


https://github.com/DannyHavenith/ws2811


At the moment, there is an off-by-one error somewhere in my chaser code that is causing an extra light to be added to the strip, which shows up as white on the left side.


My intent is to use this as an easy way to prototype LED Strip control algorithms (e.g., VU meter, frequency analyzer) before trying them in Arduino code.

Title: Re: Individually addressable RGB LED comparison?
Post by: kathy82 on July 30, 2013, 12:30:53 am
ws2811 and the ws2801 are both 8 bit per colour, the LEDs used are the same. The main difference is that the ws2811 (http://www.lightingnext.com/ws2811-neopixel-digital-rgb-led-strip.html) has the clock information sent through the data, so the chip itself doesnt have an internal clock. The ws2801 (http://www.lightingnext.com/ws2801-digital-addressable-rgb-led-strips.html) has the 4th wire for a clock as the clock is internal to the chip. This adds to costs.The other difference is that the ws2811 outputs at 18.5mA per colour as apoosed to the ws2801 which is 20mA, the difference here are really negligable and if anything under driving the LED slightly will increase the life of the LED.The ws2811 can achieve a further distance between controller and first pixel than what the ws2801 can. So the ws2811 is now becoming the main pixel type used in the hobby.  In the end most are going to ws2811 because its far better value especially in a strip
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on September 04, 2013, 11:23:09 am
Just as an FYI, I've updated my JavaScript ledstrip code, and put it up on Github:


http://dougalcampbell.github.io/LEDStrip/


And I was pleased just now to find that it got a mention on the Adafruit Blog!


http://www.adafruit.com/blog/2013/09/04/javascript-simulation-of-led-strips/


The "Chasers" and "Water Torture" pattern drivers were derived directly from Danny Havenith's example code (I crudely translated them from C++ to JS).


The "Color Wave" pattern was my own creation, which just cycles the red, green, and blue values as overlapping out-of-sync sine waves. It came out looking even better than I had hoped. And this is basically why I wanted to create the JS simulation in the first place, so I could test out algorithms easily without having to go back and forth to the hardware. I can create my basic algorithms in JavaScript, then when I have it working like I want, I can translate it into Arduino C code.


I've got an Adafruit NeoPixel Stick (8 pixels) and a couple of the NeoPixel Rings (16 pixels each), and now that I've got my new MacBook Pro talking to my Digisparks, I'm ready to play!  ;)

Title: Re: Individually addressable RGB LED comparison?
Post by: digistump on September 04, 2013, 12:10:36 pm
That's awesome dougal! Digistump will soon be stocking the WS2812Bs - the newest version of these LEDs
Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on September 04, 2013, 07:08:24 pm
Oh man WS2812B look totally rad! That is a very good development. The only thing which would make it more perfect is if they integrated the little capacitor as well, and did a version with leads, so you could do through hole or wrap the leads around a screwdriver to make loops for electrical embroidery. I am just now imagining if I could make some sort of machine so I could make those really quickly: lay an LED face down, get a small leaded capacitor, lay it diagnoally against the back and solder it in place, and then solder on two more leads for data.


I certainly have enough servos to make a soldering robot, but somehow this seems like a really bad idea. Hmmmmmmmm


I wish my 3d printer could print something which would withstand soldering temperatures. Maybe I could prototype and then get shapeways to make it in metal.


Robots!!
Title: Re: Individually addressable RGB LED comparison?
Post by: digistump on September 04, 2013, 09:55:08 pm
We'll be making some shields for them as well - which will also serve as mini breakout boards with the cap on them - possibly I'll add sewing holes as well.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on September 05, 2013, 05:55:10 am
When I saw you mention before that you'd be selling the modules, my first thought was that I should make a tiny LED matrix shield (maybe 3x3 or 4x4). :)


I've never actually designed/created a circuit board before, but this seems like it would be a simple enough thing that I could cut my teeth on. You know, in my Copious Free Time (http://www.catb.org/jargon/html/C/copious-free-time.html).  ;)
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on September 05, 2013, 10:48:12 am
Digispark + BoostMiniUSB + NeoPixel Ring = Fun!


(http://dougal.gunters.org/wordpress/wp-content/uploads/2013/09/2013-09-05-13.18.04-480x360.jpg)
Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on September 05, 2013, 05:09:27 pm
For the future if you need to boost voltages up a bit to control something like that, hobbyking sells devices which can boost voltages, I think specced at minimum 2.8 or so but I bet it'd go lower than that, up to 5v. They cost like $2 each and are already assembled.
Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on September 05, 2013, 10:41:56 pm
Nice tip - I find this 'TURNIGY Voltage Booster for Servo' for $3.37: http://www.hobbyking.com/hobbyking/store/__37813__TURNIGY_Voltage_Booster_for_Servo_Rx_1S_to_5v_1A_USA_Warehouse_.html (http://www.hobbyking.com/hobbyking/store/__37813__TURNIGY_Voltage_Booster_for_Servo_Rx_1S_to_5v_1A_USA_Warehouse_.html)
Operating Voltage : 3.2V - 4.2V
Operating Current : 1A
Max operating Current : 1.5A
Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on September 05, 2013, 10:55:06 pm
Just saw this: http://www.pololu.com/catalog/product/2564 (http://www.pololu.com/catalog/product/2564)
Pololu 5V Step-Up Voltage Regulator U1V10F5 (http://www.pololu.com/catalog/product/2564) $4.49
This tiny (0.35″×0.45″) U1V10F5 switching step-up (or boost) voltage regulator efficiently generates 5 V from input voltages as low as 0.5 V.  Unlike most boost regulators, the U1V10F5 automatically switches to a linear down-regulation mode when the input voltage exceeds the output.  The pins have a 0.1″ spacing, making this board compatible with standard solderless breadboards and perfboards.
(http://a.pololu-files.com/picture/0J4683.200.jpg?0c314b148999962e6bf1c69d5e820722) (http://www.pololu.com/picture/view/0J4683)
Also 3.3v and over 5v versions
Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on September 05, 2013, 11:05:38 pm
http://www.pololu.com/catalog/product/2115 (http://www.pololu.com/catalog/product/2115) $3.95  and compact (0.32″×0.515″), input voltage as low as 2.5 V
Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on September 06, 2013, 01:32:51 am
Great catch! Thanks for that @defragster!
Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on September 06, 2013, 02:02:02 am
@Bluebie -  :)     Anxious to see Pro&Con review if there is anything better, it seems these are small and appropriate. 
I'm wondering if there is a way to stop the draw to save a battery if you miss a change.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on September 06, 2013, 05:44:57 am
I was a Kickstarter backer for the BoostMini project, and I just received my boards a few days ago. So that's what I have on-hand. Yes, there are cheaper options, but that wasn't the point. ;D


Relaxen und watschen austounden das blinkenlights!

Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on September 06, 2013, 10:28:41 am
Interesting find @Dougal - having something to use that works is the first goal.
http://www.kickstarter.com/projects/1257390142/boostmini-power-supply-and-voltage-converter (http://www.kickstarter.com/projects/1257390142/boostmini-power-supply-and-voltage-converter)
(https://s3.amazonaws.com/ksr/assets/000/433/285/cbf072db07521ea74ad5049946b42c35_large.png?1362797280)
This was in the first 'unfunded' KStart
Title: Re: Individually addressable RGB LED comparison?
Post by: DavidWow on September 30, 2013, 10:59:18 am
Hey guys,

I have a couple projects that require chainable LEDs, but fairly spaced out (for one, I need possibly 10ft between them).  I was wondering if you knew the maximum distance the WS2811/WS2812s can be spaced from eachother, and from a microcontroller?

and/or if you can help me understand what would make a an LED circuit and its data transmission more or less reliable as far as distances are concerned?
Like, might the WS2801 somehow be more reliable because of the clock pin? 
Or do I need to go a whole different route for longer distances, like an SPI protocol, or some multiplexor??

thanx!

 
Title: Re: Individually addressable RGB LED comparison?
Post by: digistump on September 30, 2013, 06:37:22 pm
@DavidWow


First I'd say give it a try - you can these super cheap and thats always the best way to know for sure (since there isn't an official limit that I can tell)


I regularly run them 1 ft apart - but I've never tried 10 ft. I'd imagine they'll perform at least as well as SPI (SPI is often a much higher clock) and any buffer that can hit 800hz(I think?) (which should be easy) should be able to repeat the signal if needed.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on October 01, 2013, 06:54:07 am
800kHz for WS2812. I've seen references that say they might work with the 400kHz timing, but haven't tried it myself. Strips that use WS2811 controllers separate from the LEDs work at 400kHz. And of course, the WS2801s are SPI and you control the timing via clock signal.


And yeah, I think that if the signal degrades too much for that distance, a buffer could do the trick. It shouldn't be hard to find one to handle the speed, but you'll want to make sure it can also handle the current requirements. From what I understand, the WS2811/2812 modules themselves act as buffers, and re-condition the data signal on output (if I'm wrong, somebody correct me). So as long as the signal coming in is good enough, stretching things out shouldn't pose too many problems.
Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on October 01, 2013, 06:57:36 am
The datasheets for ws2812 (http://www.adafruit.com/datasheets/WS2812.pdf) and ws2812b (http://www.mikrocontroller.net/attachment/180459/WS2812B_preliminary.pdf) LED modules (the type with integrated chip, in a four or six pin LED) specifies they are good for at least 5 meters (16 feet) between each light. Each LED cleans up the timing of the signal, so you can chain as many as you want like that. Do be aware of interference though. You might benefit from using twisted pair wires, like those found in telephone cable or ethernet. Twisted pair wires will help reduce the impact of any magnetic interference on the data by balancing it equally across ground and data lines. You also might benefit from adding a resistor in between each LED along only the data lines, to help soak up any reflections in the wires which might become more of an issue at those longer distances.
Title: Re: Individually addressable RGB LED comparison?
Post by: DavidWow on October 01, 2013, 01:10:50 pm
thanks so much guys!
Seemingly encouraging responses.
So far none of you have just flat out said, 'No, it wont work',
so I feel assured!
I will definitely begin testing now.
Title: Re: Individually addressable RGB LED comparison?
Post by: carl125 on November 18, 2013, 08:49:29 pm
The WS2811 light strips I currently have are ws2811 strip which are 60 LEDs/m on white flexible circuit and IP67 waterproof silicone sleeve.

I see that they now have a new product with 144 LEDs/m ws2812, really want to take a try.

MOD EDIT: Links removed, this message is probably spam - but the 144 LED/m strips do look cool
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on December 20, 2013, 04:26:23 am
Dougal, do you have any figures on the number of failed WS2812 you found in your Ebay delivery ?

Yesterday night I finally took some time to solder 4 of mines "deadbug mode" on 2.54mm headers to plug them in a breadboard for testing, and only 2 of them are working.

It might be bad luck or bad soldering / overheating, just curious what you experienced on your side.


EdIt : oh by the way don't know if this was mentioned before, the Adafruit Neopixel library (https://github.com/adafruit/Adafruit_NeoPixel) seems to be working out of the box on a digispark to talk to those leds.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on December 20, 2013, 06:08:08 am
I haven't had a chance to try doing anything with my batch of raw WS2812 modules. For one thing, the only soldering method I have is my Weller iron, and I don't have a tip fine enough to work on small connections like that. I had ordered a new tip for working on small parts, but it turned out to be the wrong size for my iron.  :-\

I really need to look into stuff like solder paste, heat guns, and reflow ovens one of these days. But I don't see that happening anytime soon, unfortunately.

But yes, there have been several threads here where we've talked about the Adafruit NeoPixel products and libraries. For a while, I was plugging my Digispark into my car's USB power port and dangling a NeoPixel ring from my rearview mirror while I drove. I'm thinking I need to route one to the front of my car as a "Rudolph nose" for Christmas.  ;D
Title: Re: Individually addressable RGB LED comparison?
Post by: digistump on December 20, 2013, 08:35:03 pm
Out of about 80 ws2812bs I had 4 bad ones (one color didn't work) after replacing those I had more - I finally concluded that if you get them too hot the green LED goes out first, then blue, then red. Reflowing them instead of iron worked better with none dead. These were straight off the reel that I bought to sell on digistump.com.... so yeah I should probably add them to the products instead of just playing with them
Title: Re: Individually addressable RGB LED comparison?
Post by: Bluebie on December 27, 2013, 02:22:42 pm
This aligns really well with my experience with 5050 leds - you need to be quite quick when soldering them, or get an aligator clip and clip it on to the contact to try and suck some of the heat away. So make sure your soldering iron is at the right temperature and everything is working quickly before soldering those things. Also keep in mind that with ws2812 strips, the strip itself is full of copper which acts as a little heatsink for the lights. It maybe a good idea to try and design v+ and gnd traces on PCBs to work as a little heatsink if you can :)
Title: Re: Individually addressable RGB LED comparison?
Post by: defragster on December 27, 2013, 09:20:18 pm
Just yesterday I pulled this detail that might prevent the production of many future photons:

     Sparkfun Green SMD . . .   Be quick–five seconds at 260°C can cook them.

260° Celsius = 500° Fahrenheit [ conversion for those of U.S. not wanting to rush the adoption of the Metric System ]

* In 1866, Congress authorized the use of the metric system in this country and supplied each state with a set of standard metric weights and measures. In 1875, the United States solidified its commitment to the development of the internationally recognized metric system by becoming one of the original seventeen signatory nations to the Treaty of the Meter.
http://www.nist.gov/pml/wmd/metric/upload/1136a.pdf (http://www.nist.gov/pml/wmd/metric/upload/1136a.pdf)
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on January 07, 2014, 02:52:13 am
Yup that was probably my noob soldering mistake, I was using full power on my iron (450°C).

I did solder a few more since then, using less temperature (300 to 350 °C) and watching the heating timing. None failed yet.
Title: Re: Individually addressable RGB LED comparison?
Post by: Neon22 on February 10, 2014, 04:13:33 am
See new way to drive these using SPI interface and a couple of transistors:
- http://rgb-123.com/ws2812b-vs-ws2811/
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on February 11, 2014, 07:04:34 am
See new way to drive these using SPI interface and a couple of transistors:
- http://rgb-123.com/ws2812b-vs-ws2811/

Maybe I'm getting blind but I can't see anything about SPI on the page you linked ?!?
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on February 12, 2014, 11:21:02 am
I'm guessing that Neon22 accidentally pasted the wrong link, and meant to post this one, recently featured on Hackaday:

http://wiki.artifactory.org.au/doku.php?id=projects:ws2811clockshaper
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on February 21, 2014, 05:06:35 am
Thanks Dougal, interesting reading.


I took some pictures of my attempts to use those WS2812 on a breadboard for prototyping, thought I would share.


The first try was to solder them on angled headers, after bending the header's outer pins toward the middle one so they're somewhat aligned with the led pads.
This is when I burned some leds, I was using too much temperature and stayed too long on each pin because of the bad alignment with the header and they large thermal dissipation.
If I was again to try something similar i would probably use some thin wire instead of the headers.


After that I made some simple PCBs by toner transfer and chemical etching. That's already really easier to solder, but using flux is needed (mostly because of the poor quality of my PCBs).


Then I did a new PCB design adding the passive components needed to spare space on the breadboard.
That was the first time I designed a PCB for "industrial" making, I ordered those - the green ones - from seeed studio.
I realised a little too late that I put the pads on one side and the traces on the other side, with nothing linking them  :-\
To learn my lesson I used them anyway, recreating the connection with wire and components legs remnants.
Man this solder mask thing makes it so easy to solder the surface mount components ! No flux needed here.
I think this is actually faster to solder than a through hole version would be - not counting the wiring step that you shouldn't need to take if you double-checked your design in  gerber viewer before ordering...


Then I made a "final" version and ordered it from the fritzing fab service. It arrived two times faster than from seeed studio but cost me five times the price.
Now I can play with them on a breadboard :)
Title: Re: Individually addressable RGB LED comparison?
Post by: gogol on February 21, 2014, 08:06:37 am
Question: Why you have choosen the older six-pin version WS2812 and not the four-pin WS2812B, when you spent so much effort in PCBs?
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on February 21, 2014, 12:40:35 pm
I'd probably do the same thing. Why? Because I already have the 6-pin variety on hand, because I bought a lot of 100 of them a while back. :)
Title: Re: Individually addressable RGB LED comparison?
Post by: gogol on February 23, 2014, 11:58:35 pm
ok, that is one reason I have not thought upon.   I thought, that I have missed some other technical detail, making the 6-pins more valuable. ;-)
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on February 25, 2014, 05:05:25 am
Yup, like Dougal I had a stock of 100 old non-B model - I'll buy some WS2812B in the future.


By the way someone gave me the link to those adapter PCBs which seems a really cheap way of mounting those leds for breadboarding : http://www.ebay.com/itm/20pcs-SOP8-MSOP8-SOIC8-TO-DIP8-Double-Side-Adapter-Converter-PCB-Board-/390767549675
I believe it beats all the price I could get for getting my own PCBs fabricated in hobby sized amounts.

Sample picture of mouting a (non-B) led following. Could probably fit the capacitor on the unused pad if needed.
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on February 26, 2014, 06:39:40 am
Hey although he doesn't mention it, this guy is using a digispark and a prototyping shield to test those "through hole" ws2812 leds. Nice !

[edit]Ooops no sorry he actually mention digispark, I didn't read it at first.[/edit]

http://cpldcpu.wordpress.com/2014/02/18/new-member-of-the-ws2812-family/

Link found on hackaday.
Title: Re: Individually addressable RGB LED comparison?
Post by: gogol on February 26, 2014, 07:07:38 am
He is also active here in the forum, right now it seems, that he has taken over micronucleus from Bluebie. 

They seem nice, especially for projects, where you need only a small number of LEDs. However the price is heavy.  More than $1.
Compared to $0.25 per piece, if you buy 4m strips, it is really expensive.

Maybe they will appear soon at aliexpress/ebay/dx for lower prices.
Title: Re: Individually addressable RGB LED comparison?
Post by: matt79 on March 07, 2014, 11:32:03 pm
In a lot of cases, WS2812b strip (http://www.ledlightinghut.com/144-led-m-ws2812-digital-intelligent-rgb-led-strip-light.html) will refresh a bit slower than LPD8806 strips (http://www.ledlightinghut.com/lpd8806-digital-led-strip.html). The former use an 800 KHz datastream, the latter (if using hardware SPI) might be running at 1-2 MHz (it varies -- have to look at the code, see what it's doing).

Unless you have a ludicrous number of LEDs, the data transfer is rarely the bottleneck. Much of it depends on the efficiency of the code that's generating the colors. Floating point math, for example, can really bog things down.
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on March 20, 2014, 10:49:20 am
I received some WS2812B and did some breadboard adapters out of perfboard and then stripboard.
The later is far more easy to solder as the copper is not only located under the leds footprint.
Title: Re: Individually addressable RGB LED comparison?
Post by: DeuxVis on August 08, 2014, 08:02:42 am
I made a fritzing part for the WS2812B, if anyone needs it...

https://code.google.com/p/fritzing/issues/detail?id=2753#c82

Title: Re: Individually addressable RGB LED comparison?
Post by: JoeCool on September 08, 2014, 03:16:05 am
Is there any WS2811 / WS2812 kind RGB SMD LED available on the market, that is smaller than the WS2811 / WS2812 devices? I need smaller LEDs, but with same functionality like WS2811 / WS2812.
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on September 08, 2014, 09:59:20 am
For anyone who hasn't seen it yet, @cpldcpu has an article up on the APA201 modules. These are similar to LPD8806, in that they use a 2-wire SPI protocol, rather than a timing-sensitive 1-wire protocol like WS2811/2812.

http://cpldcpu.wordpress.com/2014/08/27/apa102/
Title: Re: Individually addressable RGB LED comparison?
Post by: Nick1980 on November 10, 2014, 08:32:47 pm
WS2801 and LPD8806 Based on Standard two line SPI protocol, it have higher fresh rate than WS2811/WS2812B.
WS2801 Versus LPD8806, we prefer to Lpd8806 products, its repair rate is lower, because its solder point is less than WS2801.
WS2811/WS2812B also have its advantage, Easy control and cheap price, make simple projects is enough.
Title: Re: Individually addressable RGB LED comparison?
Post by: Rickster on December 09, 2014, 10:31:31 am
Has anyone found a reasonable bulk source for the through hole (5mm) parts?

I'd like to try a light cube, but haven't found hem at a reasonable price yet.

Thanks in advance.
Title: Re: Individually addressable RGB LED comparison?
Post by: bcsteeve on June 12, 2015, 02:48:17 pm
Hi, sorry for digging up such an old post.

I found it by Google and you guys seem to know what you're talking about in this space, so figured it wouldn't hurt to ask.

I'm working on a project that retrofits into an existing device and does [whatever, it doesn't really matter].  As a bonus to users, I want to add a backlight to the otherwise unlit display.  In fact, I've already been offering this for years, but in my current redesign i'm hoping to upgrade and offer RGB functionality so they don't have to choose their backlight color ahead of time.  As a bonus for me, I don't have to supply multiple colors!

So I started looking at ICs and the only thing I came  up with was the rather expensive NCP5623.  It is ideal in that it uses i2c, which my board has readily available.  But it is expensive, as mentioned.  So I stumbled across some mention of this WS28XX stuff and quickly gather it is the control chip for common and cheap Chinese LED lights trings.  OK, it must be cheap then!  And it is... really, very cheap in volume.  That's great.  But...  is it suitable?  I'm not driving a chain of LEDs.  Just one R, one G, and one B... mixed to provide a user-selectable color. 

So I guess my first Q is:  can these work solo??  I imagine so, but maybe there's some reason they have to be in a chain.

My second Q:  for my purpose (single), is there something even better/cheaper available that I don't know about that you've come across?

Preferably I2C, but frankly I'm sure I can make any serial work.  I'm pin starved at the MCU but I'm sure I can figure something out.

Thanks!  And sorry for barging in.   Now I'm going to go check out this digistump.com site... I owe it at least that much ;)    I have to admit I had to look up "what is the name of one of Digistump's two main products" because I had no idea!  (clever anti-spam, btw... gets people like me engaged on your sales side)
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 12, 2015, 08:02:00 pm
Q1: Yes, you can use WS2812 modules individually, without chaining them. In bulk, you can probably get them for around $0.13 each (last time I checked).

Q2: You should be able to find non-addressable 5050 RGB LED modules. The WS2812s are just the 5050s, but with a controller chip built-in.

ThingM makes an I2C LED module called the BlinkM (http://thingm.com/products/blinkm.html), but it costs $15. But controlling a single RGB is just 3 pins, so only 1 more than I2C. It would probably be possible to create your own I2C LED module cheaper than the BlinkM, but I'm still not sure if it would be worth the cost?
Title: Re: Individually addressable RGB LED comparison?
Post by: bcsteeve on June 13, 2015, 03:40:46 pm
Q2: You should be able to find non-addressable 5050 RGB LED modules. The WS2812s are just the 5050s, but with a controller chip built-in.
I think I must have been unclear.  Or... well, one of us is confused anyway :)  I think when you say "5050 RGB LED modules" you're talking about the LED itself?  I'm certainly not.  I'm only referring to the controller chip (wo the WS2812, which is built into the LED body, isn't something I'm considering anyway).  What I was asking is if there is an alternative controller anyone's found that is in the same (or less) price range that is suitable for a single-output and not specialized, as these are, for chaining together.  It doesn't really matter - these are pretty cheap.


I'm suffering with their poor excuse for a "data sheet" though :(

Any anyone confirm the input voltage range?  The datasheet makes no mention of a minimum.  Has an "absolutely maximum of ~6V to ~7V" - which itself is a joke because there's no "~" in "absolute" and it can't be a range... it is an ABSOLUTE!   But to make it worse, they then show the circuit in a typical application with both a 5V and a... ehem... 12V supply!

But that's what I get for being cheap and looking at Chinese off-brand :)
Title: Re: Individually addressable RGB LED comparison?
Post by: dougal on June 15, 2015, 11:43:46 am
Yes, sorry, I misunderstood what you were asking. So I guess the most important piece of information I can give here is that you can indeed use a single WS2811 (the controller chip inside a WS2812 LED module) without chaining. It's not I2C, but it only needs one control pin, and as you said, they're cheap. Though, I didn't have much luck trying to find a bulk source of just the bare ICs. (you can get 10-packs from Adafruit.com though)
Title: Re: Individually addressable RGB LED comparison?
Post by: bcsteeve on June 15, 2015, 12:00:21 pm
Thank you.

I did find a source of the bare ICs.  You perhaps didn't see them, or ignored them, due to their 1000 pcs minimum which happens to be what I'm looking to purchase.

Incidentally... I can buy more, if people here want some?  I'm not usually in the business of reselling individual components, but if I can be of assistance...  well, people should speak up quick because I'll be purchasing fairly soon.