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Basic Electronics » 9v to vcc survivable?

February 25, 2012
by RogerFL
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Guess I was overly enthusiastic and connected the battery and only in troubleshooting realized I had the 9v+ connected to the output of the regulator rather than the input. So I guess all the power rails were 9v. When I connected correctly still nothing comes on. Did I fry my MCU and/or LCD already without seeing a thing work?

February 25, 2012
by Rick_S
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It's possible something got 'fried' but to be sure, double check all your wiring. Even take some photo's and post them here and we'll see if we see something out of whack. You may be lucky and have survived this... too early to tell though.

Rick

February 25, 2012
by RogerFL
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Here's a pic:

Link to pic

February 26, 2012
by carlhako
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Hi RogerFL

As far as I can tell you have the positive form the 9v battery going to the correct pin which is the right most pin from the angle of your picture. I can see you have the negative from the 9v battery running to either the middle pin or the left most pin of the voltage regulator I cant tell, ground should should goto the middle pin. Then I see a green wire from the middle pin of the regulator to the negative rail on the breadboard which is correct. I do not see anything coming from the 5v output of the regulator to the positive rail on your breadboard. This may be your problem as well as negative incorrectly connected from your 9v supply.

Carefully check the nerdkit supplied manual line by line and double tripple check yours against theres before connecting the 9v battery!

From your picture I would say you have not damaged anything.

February 26, 2012
by RogerFL
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That was it. Added wire from the 5v output of regulator to positive rail and everything is working great. Thank you!

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