Powering Teensy 3.2 and 144/m led strips using 5volt 10amp power supply

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derplecbob

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Hi im using a teensy 3.2
https://www.pjrc.com/store/teensy32.html

and the prop shield with motion sensors
https://www.pjrc.com/store/prop_shield.html

also im using 2 x 144/m led strip ws2812b, 5volts, soldered in parallel. cut slightly shorter so 127 leds on each strip. I need each led at basically max brightness.

I also have a 5volt 10amp power supply to run the led strips and teensy board. but I dont think the teensy can handle 10 amps so I need to wire the strips to run with 10 amps max, and also with the same power supply power the teensy without blowing it up.
 
Running 10 amp across the board would not be a great idea, so one option would be to connect the strips to the prop PCB, then the power to the strip so Teensy and strip are drawing power from the same point. Also works to provide 5V to vin and strip positive.

One related thought with 5V power is thinking about what happens when you connect USB power. You do not want the PC to be trying to power the LEDs - normal method is to cut the trace on the underside of the teensy to isolate 5V USB from 5V supply in your project but other ways to the same end.
 
Im not sure exactly what you mean. I have the teensy soldered to the propshield and the leds soldered to the propshield led driver pins. I then have a speaker coming off of the other end of the propshield where the audio pins are. and next to those pins I have a 5v and gnd wires coming off not connected to anything yet.
Here is a pic of my project. IMG_2338[1].jpg
 
So in this wiring scheme the 5ish amps the LEDs will draw flow through the propshield but not the Teensy? This is probably ok since I think the prop shield has heavy tracks joining the 5V together and a gnd plane.
 
but what if the leds end up needing more than 5 amps which from my testing so far they might be. It may be that a full 10 amps would run through the propshield, will it die? Also wouldn't the amperage run through the teensy anyways because of the solder joints?
 
if your pulling that kind of amerage over traces something is bound to heat up or burn out...
leds need a dedicated powersupply, which you can run independant of your micro or in parallel as long as it goes to the same wire attached by VIN, this keeps the “pull” at the wires and not from the MCU.
 
Thats what im thinking I need is to power it separately but still from one power source. But im still confused on exactly how to wire it. Any clarification would be greatly appreciated.
 
the data pin can goto your prop shield or teensy pin as you wish, the power and ground from your psu can directly connect to the VIN of teensy (5V psu right?) to power them, also, you use the same wires (5v remember) to go straight to the led, basically in parallel, your just splitting power and ground, one goes to your setup, other to the leds
 
and dont forget to cut the trace that links usb power with VIN, or, an alternative is to use a data-only usb cable with has no power feed, or just strip the shielding off and cut the red wire, tape it off and happy testing

this is to prevent both psu power and usb power sources from fighting each other
 
I am talking about the cutting of the 5v pads to seperate the usb and power. but I cant see where it is on the teensy 3.2.
 
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