Hi!
What's the best way to drive some Neopixel from a Feather board, it seems like there is no 5V voltage supply from the board, and the logic is 3.3v.
Boost converter + logic level converter?
Or is there any Feather 5v version in the pipe?
Thanks!
Feather and Neopixel
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- adafruit_support_mike
- Posts: 67446
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Feather and Neopixel
The techniques are pretty much the same as for the Flora.
Our NeoPixels can run from a 3.7v LiPo or a 3-pack of AA cells. In both cases, the ATmega32u4's 3.3v logic signals are high enough for the pixels to understand, and you don't have to worry about any reverse leakage from the NeoPixel strip to the GPIO pin.
If you want to use 5v power (which works better for long strips), you can use a 5v buffer like the 74HCT125 of 74HCT245 for level shifting.
Our NeoPixels can run from a 3.7v LiPo or a 3-pack of AA cells. In both cases, the ATmega32u4's 3.3v logic signals are high enough for the pixels to understand, and you don't have to worry about any reverse leakage from the NeoPixel strip to the GPIO pin.
If you want to use 5v power (which works better for long strips), you can use a 5v buffer like the 74HCT125 of 74HCT245 for level shifting.
- frickeln
- Posts: 4
- Joined: Sun Oct 26, 2014 11:52 am
Re: Feather and Neopixel
Hello !
Is it save to get the power for neopixels via the "USB" Pin on the feather-board ?
How much current can be drawn via this, assuming that the powersupply connected to the micro usb jack is strong enough ?
Thanks !
Is it save to get the power for neopixels via the "USB" Pin on the feather-board ?
How much current can be drawn via this, assuming that the powersupply connected to the micro usb jack is strong enough ?
Thanks !
- adafruit_support_mike
- Posts: 67446
- Joined: Thu Feb 11, 2010 2:51 pm
Re: Feather and Neopixel
You can power NeoPixels from the USB pin, but they might not recognize the 3.3v signals coming from the Feather's output pin. You'd want to use a level shifter for that.
The traces on the PCB aren't designed to carry a lot of power, so I'd say you shouldn't try to send more than 500mA through the USB pin.
The traces on the PCB aren't designed to carry a lot of power, so I'd say you shouldn't try to send more than 500mA through the USB pin.
-
- Posts: 21
- Joined: Mon Oct 13, 2014 10:46 am
Re: Feather and Neopixel
Hi,
I'm trying to get the 'neopixel_picker' example working from the 'Adafruit BluefruitLE nRF51' library, but can't seem to get the neopixels to light, though I can confirm the color data is being received via the Arduino Serial Monitor when connected to USB.
I have a 8 pixel stick (https://www.adafruit.com/products/1426) that I've connected to pin5 (default in the sketch) and changed NUMPIXELS to 8.
I've tried powering from the 3V pin when connected to USB and 3V or Bat when connected to a battery, but am having no luck getting the pixels to light. Any idea what I may be missing?
Thanks,
Ad
I'm trying to get the 'neopixel_picker' example working from the 'Adafruit BluefruitLE nRF51' library, but can't seem to get the neopixels to light, though I can confirm the color data is being received via the Arduino Serial Monitor when connected to USB.
I have a 8 pixel stick (https://www.adafruit.com/products/1426) that I've connected to pin5 (default in the sketch) and changed NUMPIXELS to 8.
I've tried powering from the 3V pin when connected to USB and 3V or Bat when connected to a battery, but am having no luck getting the pixels to light. Any idea what I may be missing?
Thanks,
Ad
-
- Posts: 21
- Joined: Mon Oct 13, 2014 10:46 am
Re: Feather and Neopixel
So I studied the picture of the neopixel demo on the product page (https://learn.adafruit.com/system/guide ... 1448381273) and it seemed that the neopixels were connected to pin 11, not 5. I changed that in the software, moved the wire and it works now.
You guys may want to update your library!
Still doesn't work when on battery power though.
In fact I made the LED on pin 13 light up when the device enters void loop(void), after the serial connects. It never seems to reach that stage when on battery power :-/
You guys may want to update your library!
Still doesn't work when on battery power though.
In fact I made the LED on pin 13 light up when the device enters void loop(void), after the serial connects. It never seems to reach that stage when on battery power :-/
-
- Posts: 21
- Joined: Mon Oct 13, 2014 10:46 am
Re: Feather and Neopixel
So the example 'feather_bluefruit_neopixel_animation_controller works on both battery and USB power. Here it is if anyone needs it:
https://learn.adafruit.com/ble-feather-lamp/software
Ad
https://learn.adafruit.com/ble-feather-lamp/software
Ad
- schizobovine
- Posts: 5
- Joined: Fri Mar 15, 2013 7:10 pm
Re: Feather and Neopixel
Are you initializing the serial library on startup? I was having this same problem (not running on battery power) until I realized I'd left it in debug mode, which for my code was doing:
...which, since it wasn't connected to my computer, was causing it to hang waiting for someone to pick up. Oops. >_>
Code: Select all
Serial.begin(9600);
while (!Serial)
;
Please be positive and constructive with your questions and comments.