Av switch led resistor question. .008 watt resistor?

I have looked so hard to find this answer I really have. For the led on an AV switch.... (3.7-3.3) / .02 = 20 ohms. Okay cool, but then that means I'm looking for a .008 watt resistor if I'm not using a dynaohm. I really wish I could understand this, but would I really round up to an 82 ohm 1/4 watt?

I'm using a prizm 5.1 btw. I know I could put the led on the accent led pads or maybe the power on indicator. But even with the power on indicator pad, if using a vf 3.3 led that means the equation for a blue switch led becomss (3.3-3.3)/.02....which is zero....

Maybe I'm just a big dummie, but...halp!

Well... You could either attach it to one of the pads you mentioned, or maybe use the 18 Ohm 1/4 W resistor in the store. I know I have a tutorial floating around here that covers all this. ;)

There resistor rating shouldn't be lower than you need, but higher isn't really an issue in this case. The rating relates to the power it is capable of dissipating.

Quote:

---

Originally Posted by Forgetful Jedi Knight

Well... You could either attach it to one of the pads you mentioned, or maybe use the 18 Ohm 1/4 W resistor in the store. I know I have a tutorial floating around here that covers all this. ;)

---

Okay I think this is clicking now. If I use the 18 ohm resistor, I just need to make sure I don't put full forward voltage through the led? Or will the 2 ohm difference really be negligible?

Quote:

---

Originally Posted by jbkuma

There resistor rating shouldn't be lower than you need, but higher isn't really an issue in this case. The rating relates to the power it is capable of dissipating.

---

Thank you. I'm exhausted and I forgot what I learned from tcss videos. That watts measure heat dissipation. I just can't go lower than .008 watts....which isn't going to happen