Recent content by Neme

Ok to put it bluntly, I am confused on IF I should put a resistor on my parallel circuit or not. If I did, it would be next to the battery and ONLY be 1 resistor. I have 14x total 20mA 1.7-2.2V LEDs in the circuit. I have a 2.4V battery source to power all of them (2x AA batteries). Would a...

Use the foam that is used for plants... I did an egg drop project and we used two blocks of that material, cut an egg shape into it, and filled the rest with peanut butter(so that the egg was snug against the foam. Let's just say 40ft up and throwing it straight down as hard as I could didn't...

Well I hooked this circuit up and added the 10ohm resistor and it lit up pretty bright. The only thing I'm confused on is that if I imput 10ohms into the formula I would end up with 2.8V... 10=(2.4-V_leds)/0.28 2.8=2.4-V_leds 0.4=-V_leds V=-0.4V -------------- V_total=2.4-(-0.4) V_total=2.8V...

Lets say that I am using a parallel circuit (as I have to with given space and such). I have 14x total LEDs all rated at 20mA current giving a maximum of 0.28A and max of 2.2V. My battery source is a duo pack of 2x rechargeable batteries giving a total output voltage of 2.4V. The formula...

<repost as i need answer ASAP so that I don't break the thing> so total current being the 7x LEDs per eye and 2x eyes multiplied by the current for each (20mA) which would give 0.28A. Thus it would be the voltage drop needed (0.2V) / (0.28A) which would give a 0.714... ohm resistor. Is this a...

Oh and I'm using only 1x resistor that will probably be near the batteries since I don't have room to implement it in/near the eyes.

so total current being the 7x LEDs per eye and 2x eyes multiplied by the current for each (20mA) which would give 0.28A. Thus it would be the voltage drop needed (0.2V) / (0.28A) which would give a 0.714... ohm resistor. Is this a correct calculation?

Ok I decided that I will wire them in parallel much like christmas tree lights are done. The voltage required for such a small thing is WAYYYY to much to run it in series (i can't be carrying around 50V with me everywhere for 15 hours 3 days in a row). This will allow me to actually get them...

Ok I connected them into series so the first eye would be (2.2*9+2.4)=22.2V and the second eye would be (2.2*7+2.4+2.6*2)=23V. Now when I connected the first eye to a 19.2V battery, absolutely nothing lit up. I used a meter to confirm that each LED lights up individually while connected. Do...

Ah so your saying wire them in a sort of 'S' pattern in the middle. That would make things a lot easier (except soldering the thing together but oh well).

Here is the voltage of the second eye (its more confusing) ***********[ 2.2 + 2.2 ]************ ---2.6+2.2---- [ 2.4 + 2.2 ]----2.2+2.6---- ***********[ 2.2 + 2.2 ]************* I don't have any way to replace any that break as of now and I want to power all of these together. What battery...

Ok thanks. I tried to see if a 9V(9<13.2) battery would light any of them up but not even 1 lit up.

Could you show me how you calculated that? I have one more set I have to make which will vary since I only had 20x of the 2.2V (4x of which are dead). Also, will the voltage across the top 2x and bottom 2x equal the voltage through the middle 2x and end 2x? Im trying to see what resistor...

I am currently working on making two LED eyes for a costume which needs a top row of 2x LEDs, middle row of 6x LEDs and a bottom row of 2x LEDs. I am currently trying to figure out how many volts are needed for the circuit in order to light it (at which point I can see what resistor is needed...