I'm trying to make a traffic light for the kid's 4H robotics. We have a basic python program that blinks them. They are not very bright, so I'm trying to increase the power.
If I use 5v board power with 100ohm resistor, through LED to 2N2222 with 10k ohm for GPIO to Base, it works same as just simple GPIO through LED.
I tried hooking up 9v battery through LED and NPN as before, and the LED is always on. If I increase the resistance until the LED is off, the program can't cycle the LED at all. Is the problem that the Pi ground is not connected? I'm trying to figure out how to brighten the LED, and don't want to burn my board by contacting 9v. Or is the GPIO breaking down and feeding 9v backward because it's lower voltage?
Would a diode on GPIO fix this?
Still learning, appreciate any help.
If I use 5v board power with 100ohm resistor, through LED to 2N2222 with 10k ohm for GPIO to Base, it works same as just simple GPIO through LED.
I tried hooking up 9v battery through LED and NPN as before, and the LED is always on. If I increase the resistance until the LED is off, the program can't cycle the LED at all. Is the problem that the Pi ground is not connected? I'm trying to figure out how to brighten the LED, and don't want to burn my board by contacting 9v. Or is the GPIO breaking down and feeding 9v backward because it's lower voltage?
Would a diode on GPIO fix this?
Still learning, appreciate any help.
Statistics: Posted by Fireman9143 — Mon Feb 17, 2025 7:57 pm