max302

I'm working on another little project right now (on paper as of now, may start a worklog soon), about a custom external all in one LCS, and I'm unsure about how to wire this thing. I drew a little diagram with Dia (open source, it rocks), here it is.


The x-ed out rounds represent generic 3 volt 20 mA blue 5mm LEDs. The rest is pretty self explanatory.

Looks ok according to what I'm learning in sec 4 physic's class, but the question is, will it blend? Does anybody feel like double checking?

And yeah, I know that power through 3.5 mm jack is a tad special, but I've done it before for my side panel fans, without a problem.

__________________

Armadi110

im thinking the LED's may be a little dim, maybe use 4 instead? Did you calculate the resistance required? been such a long time since i did A Level Physics ive forgotten how to lol but yes it is correct to wire them in a parallel circuit

__________________
The world rotates to the ultra heavy beat!

Xfire | My OCN Wallpaper :] | CAD Renders | Geometry Wars Thread | Gallery

max302

I calculated with this formula I got from an instructable.

R = (V1 - V2) / I

where:
V1 = power supply voltage
V2 = LED voltage
I = LED current (usually 20mA which is .02A)

5 times 20 mA = 100 mA or 0.1 A... so

R = (12 - 3) / 0.1
R = 90 ohm

Right? Will adding a resistor to the whole thing take out some juice out of my pump? Come on guys, I just need some double check on this, nothing difficult.

__________________

DuckieHo

http://www.quickar.com/noqbestledcalc.htm

Supply Voltage = 12V
Voltage Drop Across LED = 3.3V (guessed)
Desired LED Current = 20mA
How many leds connected = 5

Calculated Limiting Resistor = 87w
Nearest higher rated 10% resistor = 100w
Resistor power rating = 1.45w

__________________
To answer most of your questions: (1) a fridge cannot cool a PC (2) 64-bit OS for over 3GB or so (3) PCIe 2.0 is backwards compatible with PCIe 1.x (4) Resolution, not screen size (5) If you have a question, it is not news (6) Read TOS (7) Report, not respond to Spam (8) Uninstall nTune (9) Single/Non-Modular Rail PSUs are NOT better than Multi-Rail/Modular (10) Edward is the Law!

max302

Is it going to affect the pump? Will wiring so many stuff on one molex make it heat up with all the amperage? Was Jesus an architect? Can you balance a pineapple on your nose?

__________________