A Lux V question I haven't seen directly answered

[Kamurah]

Did the due dilligence and searched the forums but I haven't seen this answered / asked before:...please forgive if this is a noob question

Would it be possible to run this setup->

A Lux V with a buckpuck AND a MR board (for sound) using a separate 1000mah buckpuck with a dpdt switch using a single 7.2 volt battery pack?

In other words, two buckpucks wired off of the same battery pack, but one (700 mah) going directly to the Lux V, and a SECOND one inline between the battery pack and the MR board (1000mah)....

Would it work, or is this not possible due to the voltage (vice current) requirements / limitations?

Thanks for any answer on this one.

[xwingband]

What in the world would the second one be doing??? That doesn't even make sense.

[Ghostbat]

I think I understand what you are trying to do setupwise, but it should be unnecessary. The puck is there to drive the luxeon, everything it is doing to the lux is irrelevant to the board.

You would want the batteries to go to the dptd, then to the puck and the soundboard. power then returns from each to a common ground. The LED then comes out of the puck and the speaker and clash sensor from the board.

[Novastar]

X and Ghost are correct--you do not need any kind of puck to run the MR board.

However, yes... avoid giving an MR board 7.2v. At the maximum 6v--which might be pushing it.

[Kamurah]

Guys, I know this sounds a bit crazy but bear with me...

I know you don't need a puck to run a MR board....HOWEVER...you cannot run a MR board off of 7.2 volts (= fried MR board).

BUT...you need that much voltage to run the LUX V.

So what I was thinking was that if ONE OF THE TWO Buckpucks ran the LED (@700mah), then the second one would limit the voltage to the MR board.

So they are run in parallel off a SINGLE battery pack, not serial.

This way, you have a Lux V for the LED, with a MR for the sound.


So now if that explanation makes sense.....will it work or no?....or do you need a different type of voltage regulator (which is what I thought a Buckpuck was.....a voltage regulator)?


Thanks for the info

[DACOTA]

I would say you should use a resistor for the voltage drop to the mr board because a buckpuck is a luxeon driver not an adjustable voltage regulator. So calculate 5v for the mr board and just find out what resistor will drop 7.2 to 5 or 4.5 for the board then splice the batt pack wires over to the buckpuck for the led or however you do that part.

[Kamurah]

Ya...ok...but if we recommend Buckpucks here on the board because they are more efficient (and predictable) regulators than resistors for LEDs.....why won't it work as a voltage regulator for the MR board?

I mean....isn't that all a "driver" is?...other than the ones that have additional features like clash, and fade in/ fade out....


Help me understand

[vortextwist]

I don't think the puck running to the mr board is goin to work the way you think/want it to. maybe a custom batt pack.

[Ghostbat]

Hmmm... looking at the datasheet I can't see any reason it wouldn't work, but I'm not familiar enough with the tolerances involved to have any confidence and I am not convinced that you couldn't get the exact same benefits in a cheaper and smaller package by using resistors to peel off the required voltage.

But since it's your board and not mine I say give it a try and let us know how it works :)

[Steeljack]

Guys, I know this sounds a bit crazy but bear with me...

I know you don't need a puck to run a MR board....HOWEVER...you cannot run a MR board off of 7.2 volts (= fried MR board).

BUT...you need that much voltage to run the LUX V.

True so far.

So what I was thinking was that if ONE OF THE TWO Buckpucks ran the LED (@700mah), then the second one would limit the voltage to the MR board.

So they are run in parallel off a SINGLE battery pack, not serial.

This way, you have a Lux V for the LED, with a MR for the sound.

Ah. Right idea, but slightly wrong approach.

So now if that explanation makes sense.....will it work or no?....or do you need a different type of voltage regulator (which is what I thought a Buckpuck was.....a voltage regulator)?

As far as driving LEDs goes, BuckPucks are current regulators, not voltage regulators. LEDs differ from a lot of other components in that they're tolerant of a wide range of voltages, but will cheerfully gorge themselves to death on current, given a chance.

That's the bad news. The good news is that the BuckPuck also happens to include a voltage regulator which outputs 5V. That's what the "REF" line is. (The original design goal, as far as I know, was to enable you to drive a microcontroller, but the MR board is, as far as I know, tolerant of voltages up to 5.5V and so should work just as well.)

Run a line from REF to the positive terminal of your MR board, one from the negative terminal of your MR board to the negative terminal of your BuckPuck, and you should be good to go.

Thanks for the info

I hope this helped.