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post #1 of (permalink) Old 12-13-2013, 01:52 AM - Thread Starter
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Hey! Here I'll show you some cool stuff you can do with LED lighting, and how easy it is to do it yourself! I'll be showcasing 2 mods: (Monitor) Ambient lighting, and Case LEDs!

So recently, a new class of LEDs have come out, SMD LEDs (Surface Mount Device, Light Emitting Diodes), that are super cheap and easy for the end user to use. They're cheap, offer great lighting, and have basically completely outdated Cold Cathodes of old. There is simply no reason to use cold cathodes anymore, which were power hungry, used power inverters which handled some rather dangerous, inefficient, and unreliable voltages and current, and just aren't easy to work with and lacked customization.

This is different from DIP LEDs, such as these:

What LED to Buy Warning: Spoiler! (Click to show)
There's a few kits of LEDs out - NZXT's sleeved LED kits, which is 12/24 LEDs for 1/2m length of sleeved cabling with LEDs about every 3 inches. It's okay, but comes in a nice package, cheap, and with a decent controller. These use the more traditional DIP LEDs. Unfortunately, the LEDs are relatively weak, and oddly run at 5v (note - 5v LEDs do not really exist, but this product uses some large resistors and runs off 5v), and there's not many LEDs in the kit. There's the Bitfenix Alchemy, which is very pricy, and is essentially 50 LEDs per 1m LEDs sold in short strips. It's basically a worse version of what we're going to be doing, at an extreme mark-up.

So the focus is 3528 and 5050 LEDs. 3528 exists in 2 variations, 30 LEDs per 1m, and 60LEDs per 1m, the latter being a much brighter, cleaner, and consistent result. 5050 LEDs are it's bigger cousin - each LED is actually 3 LEDs grouped together (ie triple core LED, it's literally 3x 3528 LEDs in one). While they are higher performing and 'better' in a lot of technical ways, their drawback is they are more expensive, consume more power, and they are limited to 30 LEDs per 1m. So technically, while the 5050 is brighter, the 3528 is... brighter. Get it? The 5050 really shines in RGB usage (red-green-blue LED on each chip) for color change applications as well as hitting a much wider variety of colors or for a very pure color, while 3528 is better if you are sticking to a single color. In general, 3528 is the way to go with case modding, unless you want color change (which is pretty awesome, for sure).

One really cool thing about 5050 RGB LEDs though, is they often come with a remote controller to change the light colors:

The numbers refer to the dimension of the chip (not the strip it's on though), ie 3.5 x 2.8mm, 5.0x5.0mm.

Note that 3528 30LED/1m is similarly spaced as the pictured 5050.

3528 60/1m generally costs ~$8 shipped for 5m. For reference, a standard mid-atx case's height and length are ~0.5m. 5050 costs ~$15. There's also waterproof variations of both for just a couple bucks more.

There's many other varieties, like if you want super bright white, and these all come in waterproof as well to put inside custom loops or outside, but 3528/5050 are what 99% of applications need.

Power Supply Warning: Spoiler! (Click to show)
They are specced to run 12v, but they can handle about 13v, and will operate to about 8-9v minimum. This means you can't run it off the 5v rail or off 7v, for lower brightness, but you could use a non-PWM fan control to change brightness (dedicated fan controller or motherboard header). 300x 3528 LEDs is about 24w, which is 24/12=2A at 12v, and 5050 is roughly 3 times more power hungry (72/12=6A). So that's 0.2Amp/[email protected] for 1m of [email protected]/1m, 0.5m of [email protected]/1m, and 0.6Amp/[email protected] for 1m of 5050. Be aware that most motherboard headers provide about 0.5-1Amp per fan header (ie nicer/newer boards more, older boards less).

This should have no noticeable impact on PSU power consumption though. A 5m roll of 60LED/1m will consume [email protected]

The LED strips come in pieces of 3, as in 3 LEDs are mounted on every 'piece' of the strip, where there is a clearly visible mark for you to cut. You can only cut at every 3 LEDs at this specific mark. There are holes for wiring/soldering, simply attach wire in the holes, with positive to positive, negative to negative. If you want to attach more, simply add it to the end of the strip (a handy way to get around obstructions, tight bends, or simply want to continue the LEDs somewhere completely different, like in/out of the case). They have 3M backing so they'll stick pretty well to anything as long as it's oil-free (ie wipe it with isopropyl alcohol first).

Be aware that you cannot bend the strips sharply more than about 75*, or else you'll get some funky issues where some LEDs will stop working right or at all, so any sharp bends is best to simply use wire to connect 2 strips or make it a software bend.

You can hook them up to your PSU's 12v/GRND, your motherboard headers, you can hook them up to a battery pack, or a wall wart:

Just make sure the supply is 12v (or at minimum, ~9v if you intend to intentionally dim it). A 9v battery can work pretty easily, for example. Wall warts come in various amperages but as long as it's the right voltage it'll be fine. If you use like 10meters of LED as to draw enough power to maybe push a wall wart, you'll simply get a little dimming or some LEDs not lighting up. If you hook it up incorrectly, ie positive to negative, nothing will happen. On a wall wart, whether the inside/outside is positive or negative polarity, ie which is which, is never comsistent. You can buy a DC jack adaptor so your LED strip just plugs into it, or simply splice the wires on the DC jack and attach right to it.

Batteries Warning: Spoiler! (Click to show)
These battery packs you can find on ebay for about a dollar.
You can even make them on your own - even though an AA/AAA battery is 1.5v, you can hook them up to either increase voltage, increase wattage/capacity, or both, by hooking them up serial or parallel.

As for batteries, all general batteries like AA, AAA, C, D, are 1.5v, with various amounts of amperage (ie how much electricity they store, with D's having way more capacity in them than an AAA). However, if you wire batteries in 'series', you can increase the voltage, ie [email protected], or [email protected] This gives lots of options for battery power.

As for what batteries to buy, not all batteries are created equal! Basically, your common battery is alkaline, but many different types exist (Ni-MH rechargeable, and the wonderful high end Lithium Ion and Lithium Polymer), with varying amp ratings. For an AA battery, capacity ranges from ~500mah (ie 0.5amp) to 3200mah, with cheap, no-name stuff being below 500mah, but your general name-brand, ie your regular coppertop Duracells or Energizers being about 1800mah. However, batteries often don't meet advertised amp ratings, and have different discharge curves.

When batteries lose their capacity over time, they drop in voltage too. For certain on/off applications like remotes, mice, keyboards, garage door openers, this doesn't really matter, but anything involving speed or power, like the power of a light, this can suck. Most batteries, like alkalines, will typically live over 80% of their lifetime significantly below their rated voltage, ie over 80% of their life is spent 20% below capacity, ie below 1.25v. So that means your 8 batteries at 12v will become ~9v very soon. However, lithiums are great in that they survive the majority of their lifespan near their rated capacity, ie over 80% of their life above 1.4v.

When shopping for a battery, you basically choose the amps you get per dollar, but you may want a lithium if you don't want to change the batteries often in your application, or speed/power/brightness matter. You can generally find lithiums at similar value to other batteries, despite being 2-3x more expensive.

Generally speaking, the best batteries are actually Costco's housebrand alkaline, Kirkland Signature, but Duracell and Energizer's standard batteries are a close 2nd. As for lithiums, Energizer's Ultimate Lithiums at ~3200mah, they are not only the best battery, they actually come very close in value to those alkalines or the best of value batteries out there. Given that LED lighting is a 'power' application rather than an On/Off application, I'd recommend Energizer Ultimate Lithiums.

Now amp ratings actually refer to amp-hours. So a 1amp device running constantly for an hour, will consume 1amp. So 8xAA batteries at 12v, at 3200mah/3.2amp, will last 3.2 hours. So 1 meter of LED, to run along the top and bottom of the inside of your case, at 0.4amp, is 8 hours of usage. Now you might not want to use AA batteries obviously, but you might consider C or D batteries, or the various battery packs you can find out there.

Wiring Warning: Spoiler! (Click to show)
To wire the LEDs, it's best to use a soldering iron ($10+) and stranded wire (26 gauge, as is standard on computer accessories and motherboard headers, is perfectly fine), but you can use glue in a pinch.

If you use a soldering iron, really invest in wire strippers (preferably automatic, $15) and a Helping Hands ($5). It might not seem like much, but soldering without one is extremely time consuming and a little stressful at times.

Heatshrink works best to cover up the ends, if you care to, but electric tape works great too.

Incorporate a switch to turn on/off the LEDs! An SPST is all you need for On/Off, but basically any switch will work (SPDT, DPDT, etc ad nauseum). All you need to do is change from LED On to Off (more advanced switches have the ability to do things like This On/That On, but you can just leave one empty so it's still This On/Nothing On). Just make sure that the switch you get is not a momentary switch, like the kind used on computer power buttons. These switches are only on when depressed, so unless you want your LEDs to only be on when you hold a button. Momentary switches are literally just buttons, which work ideally when you just need a short zap to something - CMOS reset switches, power and reset switches for electronics, and doorbells, for example, are momentary switches.

To connect a switch, simply put the ground wire in the middle, and the positive at the end you want on.

There are just so many different types of switches, it'd be insane to list them all, but some popular choices are Slide Switch, 90* Slide Switch, DIP Switch, Rocker switch, anti-vandal (glowing ring, very cool), rotary, tactile. You really just gotta look around to see what's out there.

Everything I've mentioned here is easily available at Radio Shack, which is a rip-off. Just buy a 20 pack of switches, heatshrink, etc, for $2 at ebay or amazon or an electronics retailer like adafruit instead. Home improvement stores like Lowes also carries a lot of this stuff. They also carry LED strips, at like $50 for 1 foot though.

So my build! I'll show you 2 projects I've done:
Ambient Lighting Warning: Spoiler! (Click to show)
Simply a Dell U2312HM monitor, i took 2 strips the length of the monitor, attached it to the back, and attached to an SPST slide switch and 12v wall charger.

Case Lighting Warning: Spoiler! (Click to show)

The stick figure baby costume was done with 3528.
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