Hello all,
I have a question about how much current the Arduino can supply through it's 5V pin. I read somewhere that it can supply something like 300 mA. However hooking up a LCD Backlight display between the 5V and GND makes the voltage of the power supply go way down, which means it draws way too much current I guess. The Backlight normally takes around 120 mA so it should be fine really.
The strange thing is, this only happens when I have the backlight connected on power up of the power supply. When I hook up the backlight display later, when it's already on, everything is fine.
I don't have a short circuit in my LCD steering, because I got the same results with a resistor. I can connect a resistor of 100, 150 ohms and it does the same. Current should be 33 mA - 50 mA which is way below the 300 mA mentioned on other places.
A 10k resistor does work.
Furthermore I keep having problems with connecting to the board with bluetooth. I can connect for like 5 seconds or a little longer and it just disconnects. I know the problem isn't the bluetooth dongle, since I already replaced this one. Anyone any ideas? It seems to get worse the longer the board is turned on. I thought it could maybe a heat issue, but there isn't any compontent that feels warm really.
Maybe somebody recognizes these symptoms and can tell me what's going on. I thought maybe my board is fried, but the microcontroller itself seems to be running fine. The last program I loaded into it can drive a LCD display and works. Putting a new program is a challenge and can't be done. The connection just terminates like mentioned before.
Hope someone can help me and tell me what to do. If it's indeed fried I need a new one and I realy don't know how I did that, if it is.
Maybe somebody has some tips on how to test the board.
Kind regards,
Bluesplayer89