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vortextwist
11-21-2006, 05:46 PM
what is a buck puck. I have seen it talked about but haven't seen what it is?

Lord Maul
11-21-2006, 05:48 PM
a buck puck is a kind of saber driver. a mini puck is the same think but it can't handle as much power. the buck puck sucks all of the juice out of the batteries at a constant rate so you don't lose brightness as the batteries die like with a plain old resistor

987654321a
11-21-2006, 06:59 PM
Buck Puck-Comes in 3 different mA.
One comes in 300 mA
One comes in 500 mA
and the last comes in 700 mA ( personnally i would go with two of these, and just parallel them together.)


Micropuck-Perfect for 1w Led applications.
Its smaller than a tip of a pencil, so not only does it save space but it uses only 2AA batteries and your hilt becomes lighter. But only disadvantage is that its only good for 1w leds.


my preference-Buckpuck.



Oh and maul its not mini puck its micropuck.

vortextwist
11-21-2006, 07:31 PM
ok. but what is the function of them?

xwingband
11-21-2006, 07:31 PM
http://www.luxeonstar.com/sub_category.php?id=241&link_str=240::241

They are nice because they get more out of it and are step-up drivers. You can run an LED with under the forward voltage.

I'd disagree with countdown. You can parallel two micropucks and run a 3W or 5W. I'd classify any of the pucks in the middle. Better than a resistor, but not Corbin's or Erv's stuff.

987654321a
11-21-2006, 08:28 PM
yea but i meant with 1 micropuck i never said to not parrallel two micropucks of course it can be done and save even more space than a buckpuck but why not just go with a buckpuck?

xwingband
11-21-2006, 08:33 PM
It's smaller and if you want to get the "boost" mode which lets you under volt it, it's $10 cheaper.

987654321a
11-21-2006, 08:35 PM
oh well then thats cool. ive always used buckpucks when ive used drivers.

james3
11-21-2006, 09:46 PM
Countdown has a point when it comes to using more then one.
In that case it does make more sense to use a buck puck. The results I have had with the micro puck for the 3and 5's have been ok, not great. You get better run time with the buck and the price is the same.

Buckpucks also come in 1000ma, perfect for your blue 3w family if you arent going to live the hi-life.

vortextwist
11-22-2006, 01:55 PM
ok so I still don't understand what a buck,micro puck do?

xwingband
11-22-2006, 02:13 PM
They are drivers. They make the LED light. If you just applied power to the LED it would fry if you over volt it. Things like drivers and resistors allow you to use excessive voltage and get the max out of the LED.

If you looked at the basic tutorials you'd see the resistor. A buck or micro puck would go in place of the resistor.

vortextwist
11-22-2006, 02:15 PM
I have read a bunch of stuff before posting becouse I didn't want to look lazy but something are easier understood with a diff explanation.

chase
03-22-2007, 07:54 PM
ok, so, a puck is a driver....do you already have to have a driver for it to work? does it make the led brighter? im confused...still new to this lightsaber thing. i want to get a white led and make it purple for a custom luke body that im going to change up a little...how do i just make it crazy bright because i know it would lose light going though a filter....help?

neophyl
03-23-2007, 04:45 AM
Ok I'll try and put this in non technical terms (which is hard for me ;) )

You should all know that a led needs a specific voltage and current to work properly. That varies from led to led and the spec sheets give the values needed if you can read them correctly.

Unfortunately the battery packs that are practical to use usually dont match what the led needs precisely so we have to use other electronic parts to 'match' the 2 up.

The simplest thing to use is a resistor. These limit the supply of current to the led. Different value resistors limit for different amounts. Theres a thread on the forum that lists good values to use for different led/battery combinations. If your using a resistor go read it and use it.

The problem with a resistor though is that they are inefficient. See that power that they stop reaching the led is converted to heat. So most of it is wasted. The other problem is that a resistors value is fixed. That means it works properly ONLY with the voltage its been designed for. Change the voltage of the input and the voltage and current reaching the led changes.
Your now saying to yourself but a battery pack has a fixed voltage right. Wrong. Under 'load' ie when working the voltage drops slightly. As the batteries capacity gets lower this voltage drop gets worse. This in effect means your led isnt getting all the power it needs and is dimmer.

So for resistor pros are small size, cheap.
Cons, wasteful of power, doesnt make max use of led and batteries dont last as long.

The other choice to supply power to the leds are the 'pucks' of various types.
Now pucks contain some wondrous magic pixie dust that constantly adjusts the output to the led depending on the input voltage. Well they dont really have pixie dust but that makes as much sense to those who dont understand electronics as anything else.
The important point is that you choose a puck based on what current you want to supply (350ma, 700ma, 1000ma, 1500ma etc) matched to what your led should run at. 350ma for a 1W, 700 or 1000 for a 3W, etc.
Then you just supply thr puck with power over its minimum working voltage (usually around 4-4.5v) . It doesnt matter if your supply voltage is more as the puck will reduce the current output to a safe level for the led. As your battery discharges and the voltage drops, it just ups the current slightly so maintains led brightness. They are also alot more power effcient (usually 85-95%) so waste much less power as heat than a resistor.

So pros for pucks, very efficient, maximises battery life/run time
Cons, more expensive.

You might be asking yourself about drivers like Corbins from the shop or even Erv's buttered toast. Well they are essentially pucks but with added extras (LOTS of added extras in Erv's case). They still use the same techniques to drive the led as a normal puck.

Chase if you want a bright white then get a high code K2 (like a V00 at 120 lumens) and get yourself a 1000 or 1500ma puck. The you just need 4xAA batteries on the input and connect your K2 to the output. Instant bright white light.

Ryma Mara
03-23-2007, 06:24 AM
Wow intresting. now I understand how it works more. So what battery setups would be good for the 3W family. 4 AAA? How about the 5W Family? 6?

xwingband
03-23-2007, 07:36 AM
It most cases a volt above what you need is the best. For a resistor this is because you want the smallest value resistor possible. Remember that they're inefficient and the higher the resistor the more you are wasting that power as heat.

For drivers you need about a volt to power the PWM functions, but really having higher voltages isn't wasted. It will take the high voltage and make it current to get more out of it. That why I like 7.2V li-ions with drivers, the run time is great.

So it depends... :wink: Look at the forward voltage and add a volt.

Ryma Mara
03-23-2007, 08:16 AM
Ok so from what I can tell and if my MM to inches is right the pucks are pritty big?

What about this harness. they got 6 wires is it 2 for led, 2 for a switch and 2 for pos/neg? that right?

vortextwist
03-23-2007, 08:39 AM
i think some are but you can get them to be the size of an pencil tip

neophyl
03-23-2007, 11:17 AM
They arent that big. They can fit in a tube with a 1" internal diameter. 0.78”x 0.78”x 0.43” or 20mmx 20mmx 11mm if you use metric.

As for the ones with 6 pins you only really have to use 4 of them. 2 for power, 2 for led. The other 2 are for connecting external control devices to. If you connect the 2 spare pins together it turns the LED OFF. So its easier to just use a normal on/off switch in line with the power as usual. As with the led off with that method the DRIVER itself is still on and uses a slight amount of current. With the switch on the power lines when its off it uses zero power.

The 2 spare are useful though if you wanted to fit a dimmer as you can just connect a variable resistor between the 2 pins. Unless your doing something like that or using a microcontroller to control the led then its best just to ignore them.

Ryma Mara
03-23-2007, 12:58 PM
ok cool.

chase
03-24-2007, 05:12 PM
ok thanks. so it does make it brighter? i also have a 5w cyan led. which puck should i get for that? would it make that brighter also?