LPD 8806 and TEENSY ????

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slurry bowl

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Hello, I have been having fun using flexible LED strips with the LPD8806 chip. I am currently running them with an Arduino UNO and it works great.

I want to shrink my board down and have it be battery powered. Does the TEENSY have the ability to run on battery? If so is it also 9 V like the Arduino. Does it have Voltage out pins on it that send out a lower voltage? Which pins would a battery connect to?

Also, can the TEENSY send out data/clock pin info in the same way as an Arduino?

The strips run at 5 V. Can I use LPD8806 library like in Arduino ?

Any help or guidance much appreciated, I want to use the smallest board possible.

I know these are basic questions, so I really appreciate any help.
 
I've used the Adafruit LPD8806 library very successfully with Teensy 2.0 boards.
I haven't tried that library with Teensy 3.0 board, but the FastSPI library is even easier to program, and works really well with the LPD8806 LED strip.
The pins to use for the SPI signal are:
- For Teensy 2.0 using hardware SPI, pin B1 (#1) for clock and B2 (#2) for data
- For Teensy 3.0 pin 13 (SCK) for clock and 11 (DOUT) for data. (Maybe you can use pin 12 for SCK too, I haven't tried...)

For both Teensy2 and Teensy3, I'd recommend choosing your power supply first, based on size and weight and the battery life you want to achieve. Then figure everything else out from there. Both boards need 5 volts. So your batteries will need to supply 5V to the Teensy (at fairly low current), and 5V to the LED strip (at up to a couple amps, depending how many LEDs you want to drive). The Teensy3 has an on-board 3.3v regulator, which you could use to power any external (very low current) circuitry that needs a 3.3v supply.

Battery options would include things like:

- 4x rechargeable NiMh batteries, in series. That's almost exactly 5V. Use a diode in series to drop ~0.6 volts, and you're golden. This is what the Adafruit LED Belt kit uses. Definitely the easiest route, although quite bulky and heavy compared with some of the other possiblities.

- 1x 9V battery, and a voltage regulator. I've used several meters of LPD8806 strip from a 12v supply with a single 7805 regulator, but it needed a big heatsink to stay cool.

- Two rechargeable 3.7v LiPoly cells, in series (or a 7.2v LiPoly battery). Too much voltage, so regulate it down to 5V using something like a UBEC convertor. Or you could use a 7805-type "linear regulator", but they are less efficient than a UBEC, meaning that some larger portion of your power supply will turn into heat instead of work.

- One rechargeable LiPoly. Not enough voltage, so boost it to 5V using a voltage booster like this one (or larger)
http://www.hobbyking.com/hobbyking/...oltage_Booster_for_Servo_Rx_1S_to_5v_1A_.html

With any LiPoly option, be sure to use the right charger and an undervoltage warning system and other safety precautions. They can explode in flames if punctured or dropped.
 
The LPD8806 library works fine on the Teensy 2's. I would stick with the Teensy 2 versions, as they are native 5V. If you will be driving longer strings than you are now using the Uno, you might consider getting the ++ version with its extra RAM.

With longer strings, voltage droop becomes a problem whether you use an Arduino or Teensy: You might have to connect +5 and ground on both ends.

You can run the Teensy from battery and from a different supply than the hefty supply needed for the strip, as long as both grounds are connected.

Enjoy das blinkenlight!
 
thanks so much everyone. really just what I needed to know. Ill post updates concerning my battery selection. Appreciate it !!!!!!
 
Ive got my LPD8806 strips working with my Teensy 2.0 without issue.

Has anyone got them to work with the 3.0? Im using the LEDbeltkit example to troubleshoot, and cant seem to get the 3.0 to operate the strip.

Ive tried using static pins 2 and 3, as well as standard SPI using pins 11 and 13 as mention in this thread.

I was hoping to figure out the fastspi library but i need to get past this first.. Im getting frustrated because I know its something stupid simple that's probably holding me back
 
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