I am not sure what I have done wrong. As soon as I put power to the board the voltage regulator heats up. I have checked and it is putting 5 volts out. My LCD screen does not do anything. I do not get any black lines and it is completly blank. I had to plug it into a 9 volt adapter as my 9 volt battery is dead. Any help or suggestion would be appreciated.

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It appears you tried to post a photo... but it didn't show. Please try again, so we can see how everything is wired.

Also, in the mean time,

1. Make sure your 9V adapter has the + lead going to the input of your voltage regulator and the - lead going to your ground rail (same places your battery was connected).
2. Do not have the USB red wire connected while under external power.

I have fixed the picture. It should be working now.

I am not sure if I understand your ground suggestion. Maybe the picture will shed some more light on the problem.

Just that led with no resistor will draw a lot of current!! Heating the regulator.

I am surprised it has not burned out.

Ralph

Ok, I just put the led in there to show that it was on and I will take it out. It was still heating and the LCD was not working without the LED.

Can you confirm that your LCD contrast resistor is connected between pins 29 and 27?

I looks like it might be connecting 29 and 28, and that would be bad :D

I have checked and the LCD contrast resistor is connected between 27 and 29.

Hi Haaser,

Definitely remove the LED from the power rails. Having it there will not let the voltage across the power rails rise above 2.2V and draw a lot of current.

Can you confirm you have the right contrast resistor. It might just be the picture but it looks like black brown orange, which is a 10K resistor instead of a 1K.

I also see a black wire going into your 7805 input pin. Is that black wire connected to the + terminal of the battery?

Humberto

Yes I changed the resistor and it works now. It is hard to tell the difference between the orange and the red color.