Arduino Forum

Using Arduino => Motors, Mechanics, and Power => Topic started by: spiro_1 on Apr 07, 2013, 02:48 pm

Title: thanks for the support one reply all day long
Post by: spiro_1 on Apr 07, 2013, 02:48 pm
 Im new to ardiuno and I guess im on my own, one reply, all day

I supplied my mega 2560 with dc 12v 600 ma adaptor  to the dc plug on the board and poof. I read they can handle up to 20 v but should only use 12v, it ran fine on the usb.
but when I plugged in the 12v 600 ma power to the dc connection on the board ,it melted a little ATMEL16U2 chip next to rx/tx leds  any reason why this would happen, anything, anybody
Title: Re: mega 2560 input dc 12v 600ma poof
Post by: Retroplayer on Apr 07, 2013, 03:43 pm
Where did you supply this power (what pins/jack?)
Title: Re: mega 2560 input dc 12v 600ma poof
Post by: spiro_1 on Apr 07, 2013, 03:55 pm
the dc input jack on the board  all I did was unplug the usb connection and plug in my  ac adapor witch is output 12v 600ma I had a tft lcd running a program called stilo v3.0  aquarium controller and 3 leds on pin 8,9,10 with 1k resisters when i suppyed the dc 12v to the board the srceen started to flicker I checked the 5v on the board and it had over 7v on it and then came the smell of burning I looked at board the ATMEL 16U2 melted , can anyone tell me why it would melt that chip
Title: Re: thanks for the support one reply all day long
Post by: zoomkat on Apr 08, 2013, 04:29 am
Did you check for correct polarity of the 12v input. I think in the past I reversed the 12v input to a 7805 chip. Started smelling something hot, checked the chip and it would sizzle spit. The 12v came from a wall wart, so that may have saved the chip as it worked correctly after swapping the 12v leads.
Title: Re: thanks for the support one reply all day long
Post by: spiro_1 on Apr 08, 2013, 12:44 pm
yea the polarity is right. Crossroads told me to check the DC output on my 12v 600 ma  adaptor and I got DC 17.5v  A little high I think its no good, but still the board should of handled it.  Thanks for responding, Im new to this ardiuno, had my board 1 week and its fried, last week had rtc problem puting out 165 165 85 165 165 2165 for time and date asked everyone, read forums, finaly on this site http://bildr.org/2011/03/ds1307-arduino/#   learned that i dont need pullup resisters  and they were on the rtc had to remove them.
Thanks Alan
Title: Re: thanks for the support one reply all day long
Post by: michinyon on Apr 08, 2013, 01:05 pm
I would not be confident that the arduino can actually handle 17 volts.
Title: Re: thanks for the support one reply all day long
Post by: spiro_1 on Apr 08, 2013, 01:28 pm
yea I found that out , fried my board  :(, hope to have another in the mail soon :D
Thanks Alan