battery pack power vs. usb power

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Viedo407
 
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battery pack power vs. usb power

Post by Viedo407 »

Im having issues trying to run 73 neopixels with my battery pack (3 x D) when I plug my teensy 3.0 into my computer I get the strandtest to work with zero issues animations and all. But when I plug in my battery pack the pixels only light up white with no animations and aren't very bright at all. I checked my wiring for my battery pack but still cant figure it out. Any ideas would be great. My deadline is fast approaching and im getting a little nervous.

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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

[Moved from Test Messages to Glowy Things]

Please post photos showing how you have it wired.

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Viedo407
 
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Re: battery pack power vs. usb power

Post by Viedo407 »

Absolutely, I will do it a.s.a.p. sorry for the late reply. Work is getting in the way of my pixel journey.

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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

Are you connecting direct from the Teensy, or via a level converter? https://www.adafruit.com/products/1787
The Neopixels like to see a control signal pretty close to the supply voltage. I suspect that your battery pack voltage may be just a bit higher than your USB voltage.

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Re: battery pack power vs. usb power

Post by Viedo407 »

Here is how I have my battery set up to the teensy. Two wires from each battery pack (+ & -) split into the ground and 5v directly with a with pin1 going to the 73 leds. I dont have anything else connected.
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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

Measure the voltage between the GND and +5v pads at the start of the strip with the battery pack and when powered via USB.

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Re: battery pack power vs. usb power

Post by Viedo407 »

I get 4.21 dc volts peak on the battery
and 4.78 peak on the usb power

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Re: battery pack power vs. usb power

Post by Viedo407 »

But as the animation plays it goes up and down

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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

But as the animation plays it goes up and down
Since animation doesn't work with the battery pack, does that apply to the USB power only? What is the approximate range of voltage fluctuation?

in your diagram, you show power and GND going directly to the Teensy, then from there on to the strip. Generally, it is better to run power to the strip directly and branch from that back to the Teensy. Since the leds are a substantial load, you do not want to have a voltage drop on the ground wire between the Teensy and the strip.

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Re: battery pack power vs. usb power

Post by Viedo407 »

For the usb the flux ranges between 3.98-4.78
While the dc remains constant at 4.21

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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

I'd try wiring the power to the strip first. If that doesn't help, a level shifter may be the solution. This is the one recommended by the manufacturer of the Teensy: https://www.adafruit.com/products/1787

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Re: battery pack power vs. usb power

Post by Viedo407 »

I got the lights to work on the battery pack. I just removed my power and ground and moved it to the END of the strip instead of splitting it between the teensy and the beginning of the pixel strip. Good call!!!! Thank you very much for taking the time to help. Im sure ill be back soon with more questions. Just out of curiosity what language am I programming in? (Reverse engineered "strandtest") lol

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Re: battery pack power vs. usb power

Post by adafruit_support_bill »

language am I programming in?
The "Arduino Language" is a derivative of C++. The Arduino pre-processor that goes through your code and automatically generates the header files, so it is a little less verbose than raw C++.

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