Dead pin teensy 3.6

[ted]

Hi!

I accidentally shorted one of the digital pin (RX3) of the teensy 3.6.
And now my teensy not working at all. Is it possible that the whole cheap destroyed?
How can I test it?
And what circuit should I use to avoid again?

More info:
Connecting the USB, i got 5V on GND and VIN pin.
on 3.3V i got 0.3V

If I connect the teensy GND to an ardunio, and the teensy's 3.3V to the arduinos 3.3V, and the arduino is connected to the USB the leds on arduino turns off.
If I disconnect the teensy from arduino, the led of arduino again turns on.


Thanks!

 

[GremlinWrangler]

Sounds like there is something on the teensy board that is drawing too much current. So the onboard 3.3V regulator is failing down to 0.3V, and your Uno gave up for the same reason. Unfortunately this is most likely the main IC which isn't really replaceable, and even if it is then would be much of the cost of a new board.

To check before binning it is to check there there really isn't anything shorting anything else at the moment, then press the program button and plug it in. If your PC registers the new USB device even briefly then you might be able to get blink onto it and get rid of whatever code is causing problems. More likely though shorting a pin set to output killed the chip, possibly simply by shorting both the transistor trying to pull up and the one pulling down, possibly by something more esoteric.

Main thing is to avoid shorting things, and if you want to be safer a 20ohm resistor in series with pins intended for outputs will reduce the potential for problems (though also limits what the pins can do). Still not immune to shorts (it's 10 times the rateing) but may give you enough time to work out something isn't right, or at least constrain damage to a single pin.

And if your short was to 5V rather than another pin then T3.6 is very much dead.

 

[ted]

Ok, thanks for the info!

Sounds like there is something on the teensy board that is drawing too much current. So the onboard 3.3V regulator is failing down to 0.3V, and your Uno gave up for the same reason. Unfortunately this is most likely the main IC which isn't really replaceable, and even if it is then would be much of the cost of a new board.

To check before binning it is to check there there really isn't anything shorting anything else at the moment, then press the program button and plug it in. If your PC registers the new USB device even briefly then you might be able to get blink onto it and get rid of whatever code is causing problems. More likely though shorting a pin set to output killed the chip, possibly simply by shorting both the transistor trying to pull up and the one pulling down, possibly by something more esoteric.

Main thing is to avoid shorting things, and if you want to be safer a 20ohm resistor in series with pins intended for outputs will reduce the potential for problems (though also limits what the pins can do). Still not immune to shorts (it's 10 times the rateing) but may give you enough time to work out something isn't right, or at least constrain damage to a single pin.

And if your short was to 5V rather than another pin then T3.6 is very much dead.