I'm having a hard time understanding these things.
Here's my situation:
I have 10 white LEDs. I bought them from China, and they have no rating and no one knows for sure their maximum voltage or amperage.
I'm using a 5V, 500mA power supply.
I first wired them in series of 2 and then in parallel (I hope I'm using at least partially the right terms), like this:
I didn't use any resistors because this should only apply 2.5 volts to each LED, and a white led is usually 3 to 4.5 volts? Right?
But the light was very dim, so I rewired everything in parallel and applied the full 5 volts to them.
Now I'm happy with the brightness, but the hot glue I used to attach them to the board melted.
So the question is, is the glue gun the wrong glue to use, or are they getting way too hot?
The amperage should be ok, 10 LEDs x 20mA should only draw 200mA, way below the 500mA the power supply can supply, or did I get this wrong too?