This is my first post in the forum, I hope that I am following properly the rules.
I am powering my Arduino Uno with an external power source at 9 V using the Vin input. Then I am using the 5 V output to power the Blacklight LEDs for an standard LCD. The problem that I have is that when the Backlight is connected, suddenly the Power Source supply drops from 9V to 5V.
Nothing else is connected to the Arduino, just the Power on Vin, GND and the backlight for the LCD.
Any idea about what can be happening?
Thanks a lot.