Which resistor should I use?

[War Machine]

Ok so my current build uses a Tri-Cree Red/Red/White set-up (Reds in parallel each with a resistor, White is for FOC). I need advice on which TCSS resistors to use.
Battery = 3.7v Panasonic 18650
Board = Nano biscotte V3

Reds: 2.59V @ 1000mA

R = (3.7v - 2.59v) / 1A = 1.11 ohm
P = 1.11ohm * (1A)^2 = 1.11 Watts

Is it ok to overdrive the reds slightly by 110mA using a 1 ohm, 2Watt resistor? Or should I just go 1.2 ohm, 3Watt ?



White: 3.15V @ 1000mA

R= (3.7v - 3.15v) / 1A = .55 ohm
P = (.55 ohm) * (1A)^2 = .55 Watt

Do I round up to the 1 ohm, 2 Watt which will probably cause dimming of the LED, or overdrive slightly by using the 0.5 ohm, 3 Watt ?


Thanks guys!

[ColdVizjerei]

Better safe than sorry so good practice dictates that you do NOT overdrive your LEDs.

Go with the 1.2Ohm 3Watt for the reds and 1Ohm 2Watt for the whites.

[War Machine]

you don't think the white LED will be way too dim by almost doubling the resistance needed?

[ColdVizjerei]

It should work out alright.
If you're still afraid the white would be too dim you're going to have to get your own .55ohm resistor since I don't think TCSS carries that.

[Generic Jedi]

I have a GGW LED, and I'm using a 0.5 ohm 3 watt resistor for the white LED.

If you are going to use white as a main color, use the 1 ohm resistor. If you are using the white for FoC, you can overdrive it a little bit because when it's on, it won't be on that long.

[ColdVizjerei]

If you are going to use white as a main color, use the 1 ohm resistor. If you are using the white for FoC, you can overdrive it a little bit because when it's on, it won't be on that long.

^True. Totally forgot about that.
Tho I'm still going to stand by rounding up just to be safe.

[Greenie]

White washes out other colours anyway so for FOC you won't even notice if it's a touch dimmer