I have the following setup and noticed that lately they are taking longer to turn on.
I have 2 LED’s, they are 20mA / 3.2v
Im using a resistor with these specs 200ohm/500mW/1/2W/350v
Running on a 9v battery and a toggle switch in line to turn on and off.
I know that the recommended resistor is a 130ohm, but was looking around and asked and was told a 200 would just use less power.
From what I recall, when I got it all setup, I could turn it on and off and everything was almost instant. But now when you turn it on, it takes about 3 to 4 seconds to turn on, they aren’t slowly turning on, they just lag that long to come on.
Is there something I can check in my setup or do differently to make it almost instant on and off?
Its for my nephews iron man helmet, we have 2 leds powered by the 9v and a little toggle switch to turn it off and on… it makes the eyes of the helmet light up…
Im game for swapping out the power to other batteries or whatever it would work best with…
I would go with 4 AA, but if size is an issue, go AAA. These would have 100 times more capacity and should last a while. The only problem is the 4 AAs would only supply ~6V. So you would need to run the LEDs in parallel. You will need another resistor for the second LED. You can use your single switch for both still. Depending on your LEDs, you might have to drop the value of the resistors, but I would check to see how bright they are first.
You can also get a battery holder to make wiring easier. Some even come with a built in switch so you could keep everything contained. This is the [3AA version. I seem to be unable to find the 4AA version. Pretty sure I bought mine from here, but you can find them on Ebay too. The 3AA version should work as well.](Battery Holder 3xAA with Cover and Switch - Bare Wire - PRT-10891 - SparkFun Electronics)