Teensy3 + RGB strips wiring

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Senescence

Senescence

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Hi,

I'm starting to test the wiring of my set up and i'd like to start following the OctoWS2811 tuto on the website.
But i do not want to cut apart the VIN and VUSB pads, in order to be able to use my teensy for other applications.
I got an external 5V power supply and i'd like to supply my RGB led strips directly without using the VIN of the teensy.
But then how do i wiring the grounds of all my strips with the teensy ?

And also, my power supply has a 110/220 v GND ... is it important to plug it ?
I almost dont have GND plugs at home ... :/

Can someone help me with this ?

Thanks a lot
 
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Don't get it. I managed to do everything correctly on Arduino UNO and control my 3 X 60 leds strips ...
Once on the teensy, i followed all the instructions from Octo2811 ... and fried my 3 strips ... I have no led working anymore ... :(
 
I'm not sure I fully understand your questions, but I'll attempt to weigh in:

- It sounds like you're using a power supply that most certainly needs a GND.

- If you want to power your teensy off of the power supply, then you must cut VIN/VUSB as directed. If you just want to power LEDs from the power supply and power the teensy off of USB, then you simply leave the pads un-cut. Just make sure you're not connecting the +5 from the PSU to the VIN on the teensy.

- Connect the +5V/GND of the strips directly to the power supply. This is where I'm not sure if I'm understanding your question... +5V and GND get powered by the power supply, DIN connects to one of the pins on the teensy, and (optionally, depending on grounding issues) DOUT goes back to GND on the teensy. This is well-documented on the main OctoWS2811 page and in multiple posts on this forum:

Code: 
+5V (from PSU)    ----|            |
DIN (from T3 pin) ----|  LED STRIP  | --- DOUT (back to T3 GND)
GND (from PSU)    ----|             |



I have no idea why your strips burnt out. FWIW, if they're the model WS2812B, then it's probably only the first LED in the strip. I managed kill off a number of LEDs due to a variety of newbie mistakes, and in all cases the first LED in the strip took the fall, leaving the rest of the LED's un-harmed.

FWIW, I am powering my 4 teensy 3.0's off of USB and powering the strips off of separate PSUs and have eliminated most of the glitching I was seeing. I did end up running a wire from the GND of the teensy to each of the 6 power supplies -V terminals ~instead~ of running DOUT back to the teensy. Doing both at once actually resulted in more noise for me.
 
Oh, sorry to hear you lost so many LEDs. That really sucks.

I can't know what went wrong, but I can tell you I personally fed all sorts of horribly wrong data into my WS2811 strips while developing OctoWS2811 and also the Teensy3 code in Adafruit's NeoPixel library. I've never physically damaged a WS2811 only by pushing wrong bits or wrong timing into the data pin.... and believe me, I did a LOT of wrong stuff and tried all sorts of timing while developing the code.

Incorrect power connection is the likely cause for destroying parts.
 
Thanks guys !
I just checked ! As Tetsuo said, only the first LED of each strip is dead ... phew ! I can keep playing ! ;)

But now i really don't get what is wrong with the wiring with my Teensy 3.0. It seems i do all fine ...
But when i try turning a strip on with the basictest of the OctoWS2811, half the strip turns on ... on very bright white. And when i turn it off, it won't turn on again and the first Led will be dead ...

I have NO CLUE what is causing this !

With arduino, i'm making a mess and it's working all fine with ada's libs.

But i'd much more prefer to use teensy than arduino :(
 
@Senescence, the only time my ws2811 array went all white was when the bridge between pins 15 and 16 was not good. Might be worth checking.
 
I originally purchased 1920 LEDs from Ray Wu on Aliexpress, pretty much only for developing and testing OctoWS2811. I made the mistake of not buying any spares.

As you can see in the OctoWS2811 photos and video, early on I had 1 LED die on the 6th row, taking out the rest of that strip. Shortly afterward, 2 more developed problems, where they would work for a while. One would "die" in just a few minutes, the other about an hour. Both would "reset" after leaving the entire thing powered down for a few hours.

While developing a live webcam and GIF animation player for Maker Faire, I had a few more LEDs die. By then, I'd ordered another strip to use as spares. A couple days before taking it to San Mateo, I cut out the dead pixels and soldered in replacements. Here's one:

mf2013_4.jpg


While at Maker Faire, yet another pixel died, but luckily it was on the bottom row, so few people noticed. On Sunday morning I got into the Faire early to allow time to replace it before huge crowds came. While talking about it to someone, I pointed and mistakenly touched the dead LED, and it started working again!

It seems much of trouble has been the solder joints physically breaking. Another thing I noticed after running the LEDs all day in the summer at Oregon's Mini Maker Faire was the strips were bowing a little between the parts with double sticky tape. The LEDs heat up, partly from the LEDs, partly from the hot weather, and it seems the strips are bending a little from thermal expansion, and the pretty rigid mounting I used.

This same LED board was used at one other event called SOAK, which is Oregon's regional Burning Man weekend camping event. It ran for 2 nights, about 10 hours each, without any LEDs failing. That was outdoors and it was fairly cold both evenings. That further leads me to believe the problems are temperature related, perhaps due to the flexible material, well, flexing as it heats up and thermally expands and bends slightly between those places where the tape holds it rigidly to the wood.

If I ever build another one of these LED boards, I'll probably do it very differently, but I'm not sure exactly how.

My gut feeling is the newer WS2812B with only 4 solder joints might be more reliable, since there's fewer mechanical connections to fail and they're spaced farther apart.
 
mortonkopf said:
@Senescence, the only time my ws2811 array went all white was when the bridge between pins 15 and 16 was not good. Might be worth checking.
Click to expand...


So ... that happened to me !
It was all white ... when i forgot to connect 15 and 16 together !
But as soon as i connected these pins together, the strip flashed and went off ... with the first led fried ... and this happens everytime i try pluging it again :'(
 
PaulStoffregen said:
My gut feeling is the newer WS2812B with only 4 solder joints might be more reliable, since there's fewer mechanical connections to fail and they're spaced farther apart.
Click to expand...



I think so too.
So, i'm discovering the joys of cutting and replacing :D
I guess i'll develop my stuff with these chinese leds and once i get there, i'll just replace with better ones ...

But in my project, the led strips are just gonna be used on stage for concerts ... So, it's like 45 or 50 minutes ... with maximum 2 leds on per strip at the same time ...




Could someone show me the set up of the led strips with teensy for octo ? But like ... an example ?
Cause i followed all the instructions carefully and it seems i'm too dumb to be able to do it ... I'm missing something and i fry my leds ...
 
@Senescence. This is a bit embarrassing, but here you go, an image of my "Heath Robinson contraption" setup for the teensy3.0 and octows2811. This is running a small array of 8x34 pixels. All the led strips use a common ground and this is also common with the Teensy. They are joined by the battery terminal. All the led strips positives are common to one wire which also feeds the teensy and this is joined to gether by the battery. As these strips are short and don't require much juice, i did not bother feeding additional supply or connecting at the far ends to ground either.The resistors are 100Ohm. This is not the best solution, but it works for me. All runs from 4xAAA batteries for a reasonable time. Sorry about this disgraceful display of spaghetti, neatness has never been one of my things.

teensy wires.jpg

here is an image of the soldering i had to do to remove the bad sections of the 144led/m strips for a different project. These are now encased in a clear poly tube.
soldering.jpg

with regards to your leds popping, what power are you supplying them with, might be worth getting a meter on it, as it sounds like you may be electrocuting the poor things. These are 5v pixels aren't they?
 
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Senescence said:
I guess i'll develop my stuff with these chinese leds and once i get there, i'll just replace with better ones ...
Click to expand...

I'd love to be wrong on this, but I don't believe that there ARE "better ones". I've ordered from three different vendors on aliexpress as well as from adafruit... all WS2812b strips appear to be fundamentally the same. I did get a batch where the solder pads had a darker tarnished look, and some batches' white paint on the flexible PCB is less durable than others, but overall they're the same in terms of failure rate.
 
Yeah, they all seem to be made by the same 1 or 2 factories in China.

But there are people making more expensive WS2811 products on rigid PCBs. Those probably have different reliability.
 
I had the same issue with the first led dying on several strips. I'm not sure what went wrong exactely as I had pretty stable 5v output...
 
Things that kill the first LED include, but are certainly not limited to:
- shorting +5V to DIN (very easy to do with a probe if you're testing at the pads on the strip)
- crappy and/or overloaded PSU
- getting the first LED too hot (I managed to do this by trying to power too many LEDs from a single pair of 20AWG conductors... the wire was quite warm to the touch but not alarmingly so... apparently it was enough to warm up the first LED, at which point it seemed to self-perpetuate, getting hot enough to burn out)
- static discharge
- giving them dirty looks

OK, the last one is just a guess for a couple unexplained LED deaths :)
 
Hey guys,

Thanks a lot for your help !

Here's a picture of what i tried to do ...
Can you help me finding what i did wrong ?

As said by someone before this post, shorting 5V with DIN would be the explanation ... but i don't see where that happens in my wiring !
I'm not using the +5v of the Teensy ... only the 5V of my power supply ... which seems very stable btw ... after testing !
And as indicated in the octo tutorial, i'm connecting the GND of the teensy with the GND of the led strips and GND of the power supply ...
DIN is connected to PIN 2 here as i'm testing with only one strip ...
Pins 15 and 16 are connected together ...

So ... when i do this, in turn on the power supply and the strip flashes and first led burns ...
 

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Your power supply doesn't appear to be grounded. Also, it's difficult to see the PSU labels from the pictures, but if you're connecting anything from the teensy or strip to the AC ground on the PSU, that's certainly not the intended GND! There should be a V+ and a V- on the PSU - the "V-" is the GND you want for your 5V circuits.
 
My power supply is not grounded cause i have no ground at home in the plugs :(

There is nothing connected from the PSU ground ... The GNDs of teensy and strip are connected to COM/-5V of the PSU ...
 
I just tried a similar setup here. Seems to work fine.

ledtest.jpg

One thing to try is decreasing the power supply voltage. Yours looks like the same model. That little "+V ADJ" pot can adjust the voltage. Lowering it to about 4.6 or 4.7 might help the WS2811's to receive Teensy3's 3.3V signal.

Of course, the best way to drive these LEDs is through a 74HCT245 buffer that increases the signal to 5V.
 
Thanks a lot, paul.

I already lowered the voltage. It's about 4.8 right now.
You said that it would help the strip to receive Teensy's 3.3V ... but that's not supposed to happen right ?

On your setup shown in this pic, are VUB and VIN still soldered ? That wouldn't change anything in my situation, right ?

I really don't get it.
The exact same setup on Arduino works all fine :(

Could it be my Teensy that has a problem ? Like it would supply the 3.3V to the digital pins ?

What library and code example are you running for this test ? So i can recreate the exact same conditions ...
 
@ senescence, what is the role of the 4700 cap? not too hot on electronics. So, does the same thing happen when using the teensy but drawing the power from a different source? You could try a small battery pack (4 xAA or AAA) and run the leds and the teensy from a joint connection, this is just to rule out coding or the teensy. I would set up a testing process at this point.
you should already have the basic test sketch in your arduino library (file/examples/Octows2811).
LAstly, the colour scheme of the wires on my ws2811 strips was all about face - green was 5v, red was data and black was ground. I realise that this was not an issue for you w=as you got the leds to work on an arduino, but might be worth checking one more time...
 
Good idea ! I don't have batteries at the moment but it's worth trying !

I tried with the basic test sketch from octo library. That's how i burnt the leds.

The capacitor ... Well, someone told me that it was always good to use one ... just in case ... as i had one i put it there.


Yes, i also checked twice the wires ... and colors ... But i checked carefully how they are soldered and there's no pb there :(
 
Senescence said:
On your setup shown in this pic, are VUB and VIN still soldered ?
Click to expand...

Yes. In this test, I used a Teensy 3.0 with pins, in the original condition it comes from PJRC.

That wouldn't change anything in my situation, right ?
Click to expand...

Yes, it absolutely would. If you cut apart VUSB & VIN, the Teensy 3.0 can't work at all in this test. There's no connection in this test from the power supply to VIN, so the Teensy would be without power. You wouldn't even be able to upload any code to it.


What library and code example are you running for this test ? So i can recreate the exact same conditions ...
Click to expand...

I ran File > Examples > OctoWS2811 > BasicTest

I tested with Arduino 1.0.5 and the latest Teensyduino 1.18-rc1. But if you're using Teensy 3.0 (not the new 3.1 board), any 1.16 or 1.17 version should be the same.
 
Thank you.
I lowered the voltage down to 4.8. I tried it all again ...
Nothing happens.And first LED burnt again.
Only explanation i have : my teensy is dead or something is wrong with it.
Tried again on arduino : all good.
Might order a new teensy from the website here i guess ...
I'm going crazy with this :/


I would start doing all my project with Arduino but i really prefer teensy ... brrrr
 
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I am sorry to the thread starter if you would call this a hijacking, but I have a very similar issue myself.
Maybe I need it in with a silver spoon:p

To go over to purely external power doesn't seem too easy for me either.

I am using FastSPI_LED2_RC2 example Fast2Dev to start with.
The Leds are 150x ws2811.
What was used was Teensy 3.0, Arduino 1.0.5, Teensy Loader 1.15 under OS X.

When I run it from usb power, it all works fine, but when I try to use the power supply (check pictures) the led flashes for a second then nothing.

I tried hooking it up in two ways:
i.
V- psu -> teensy gnd -> led gnd
V+ psu -> led +5V
teensy pin16 -> 220 ohm -> led DIN
usb power -> teensy microUSB

ii.
V- psu -> teensy gnd -> led gnd
V+ psu -> teensy Vin -> led +5V
teensy pin16 -> 220 ohm -> led DIN
(this section should require cutting something something, but check on the pictures if I have done that, because I simply never really understood what to cut)

Both methods yield the same result.
No leds get fried, and teensy keep working, so hardware error I don't think I can blame it on.
It has to be my novice wiring for sure;)

Here are some images:
http://imgur.com/BEX0K8W,Y0pzf96,qX0ZKVx,BkTkpLn,wppxGir

Note.
The power supply is measured to 5,13V.
 
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