Shortened pins on Teensy LC

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lalous

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I am doing a simple sound reactive project. It was working perfectling for like 1 minute after I was done soldering everything in place, when suddenly the lights of the LED strip started getting less bright. I instantly turned everything off and the boost converter was really hot. Basicly I use a 3.7v Battery and boost that with a step-up converter to 5V to power up the LED strip and Teensy LC. When I tried to plug the Teensy in the computer it wouldn't connect and the teensy loader wouldn't recognize the device either. Here is the message that I got on the Arduino IDE:

"Teensy did not respond to a USB-based request to automatically reboot.
Please press the PROGRAM MODE BUTTON on your Teensy to upload your sketch."

So I can't power up the teensy from the USB port, but when I plug in the batttery, it lights up and detect the sound from the microphone because I see the built in LED lighting up when i make some sound, but the step up converter (rated for 2A) gets really hot. It felt like there was a short circuit somewhere. When I cheked the PCB, everything was fine. But when i checked the pins on the Teensy LC, the Vusb, Vin and Ground were shorted. Is there a way to fix it ?
19204824_10154465039326861_1057531673_o.jpg
 
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If it functions on battery power your CPU is most likely still OK which is a plus. The USB failure is probably because your PC detects more than 0.5 amps being drawn and shuts it down. So it's a case of working out why Vin is shorted to gnd. Vin and Vusb are supposed to be connected unless you have cut the trace to isolate these for battery operation.
 
No i haven't cut the trace to isolate the battery, because I make sure of not using both at the same time.
 
Looking at your photo, is there a pin in the VUSB hole, and how is it seperated from the Agnd pin next to it in the proto board?
 
I cut the trace between Vusb and Vin. And the short circuit is between Vin and Ground now. The teensy still doesn't turn on when plugged with a USB. When i powered it with a battery, it turned on and worked, but the CPU started to get really hot. So I unplugged everything.
 
Here is a schematic of my circuit. It could be my circuit that broke the teensy, so I wanna make sure it won't break another teensy when I plug in another one.
Circuit_Mic.PNG
 
Do you have anything limit current through the base of the transistors?

As it stands you'll be pulling massivly more current than the pins can handle through there, and possibly destroying the transistors.

Does your RGB strip have resistors on it?
 
Sorry, yes there are resistors on my RGB strip. I will add like a 3k Ohm resistor between the base and the ouput pin to limit the current to. Do you think that is what caused the teensy LC to break ? The 3.3V and the ground are shortenend. What do you think could have caused that ? Because everything was working great, and suddenly, after like 1 minute of usage the LEDs stopped working properly and than I couldnt connect the Teensy to the computer.
 
The drive through the transistor base will have certainly been abusive and running for a minute or so would have been possible through the diode, failure may have shorted the output drive stage inside the IC. Unsure if you said anywhere if you'd attempted disconnecting your outputs and checking then, since it's possible only have the low side driver dead and you can just isolate the pins and keep using it, at least for testing.

It's also very possible your transistors are toasted as well, so check those with multi meter before moving on. On the diode setting base/emitter should be about 0.5V. With teensy in circuit that changes a bit, but if it's powered off and healthy some should be true.
 
While it won't hurt Teensy, those 220 ohm resistors will rapidly drain your battery.

Your diagram shows a transformer, which doesn't work with DC voltage. Transformers are only for AC. Maybe it's really something else, like a DC-DC switching power supply? Just a guess from so little info. If this really is just a bare transformer, obviously DC voltage applied to its windings will not work.
 
It is a DC-DC step-up converter. It was all I had to do the schematic. Do you think something here could have fried 2 of my teensy LC. When I plug in the batterie, it looks good. The problem is the moment I did a sound, the RGB strip lit up, but the Teensy was really hot ! and suddenly it stopped working and the pins were shorted
 
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