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I plan on connecting 8 LEDs in parallel with 3 AA alkaline batteries (i.e. 4.5 volts) being the power source, and only one 230 Ohm resistor. The circuit is really simple/generic, so I assume no schematic is needed. The issue that I'm facing is that the more LEDs I add in parallel to the circuit, the dimmer the rest of the LEDs become. This is the kind of behavior one would expect if the LEDs we're connected in series, so I am a bit lost. It would also be worth mentioning that I also tried using a battery pack (the ones for phones) with an output current of 2A, but the results were the same.
Thanks for the help!