Voltage Regulator or other device

**Jase Kala Maris** · 06-18-2009, 12:21 PM

Is there something like a Voltage Regulator that will Limit the Voltage so you don't go over a certain Voltage?

The Voltage regulators I've been looking at seem to only work correctly if you put a certain range of voltage into them to get the regulated voltage out.

EX a 12V regulator needs like 13-15 volts in to keep the voltage out at 12v consistently.

I just want something to limit the voltage to no more then 12v max.

EX if I have 3x 3.7 V batterys in series and get an average of 11.1v but they can peak when charged I've read to like 3x 4.2 or more and I don't want to go to high.

I'm guessing there is something out there like this but I don't know what it's called and without the name of it my google searches haven't been very fruitful.

could someone help me out?

**Eco** · 06-18-2009, 01:53 PM

I believe you are looking for a buck-puck, or driver board.
http://www.thecustomsabershop.com/Hi...onics-C17.aspx

**Jase Kala Maris** · 06-18-2009, 08:08 PM

nope but thanks.

I want something to cap out the voltage on a battery back before it goes to a driver board...

for example 15v outta a battery pack would fry a ultra sound board so I want something to put in between them to only let 12v pass through to the driver.

I'm still a newb so maybe I'm just not explaining this well enough...

A voltage limiter....

**Eco** · 06-18-2009, 08:49 PM

Oh.
I see what you're after now.

Why are you using 15V?

12V is the maximum for US 2.0, that means as long as you have enough voltage for your LED, you don't need to max out at 12V.
Two 3.7V trustfires should be sufficient for any application you've got in mind.

**Onli-Won Kanomi** · 06-19-2009, 12:23 AM

Not if he wants to run a tri-rebel wired in series with the Ultrasound in which case a 2 AA holder with Trustfires isn't enough and a 4 AA holder with Trustfires is too much and a 4 AA holder with 3 Trustfires and a dummy AA is fine if delivering the nominal voltage but can peak over the Ultrasounds 12V max when just charged...I'm guessing that that is why he might want a "voltage regulator"/"voltage limiter" that prevents voltage over 12V but still allow voltages under 12V through?

**xwingband** · 06-19-2009, 09:07 AM

So the goal is to not regulate under 12V and regulate above that?

**Jase Kala Maris** · 06-20-2009, 08:22 PM

yes, pretty much.
I want to run 3 x3.7 volt batteries but not for a tri rebel for an led string running in series and parellel. Split the strip up into 3 sections running 3.4 volts and 1000mah and have enough for the us2.1 to run well and get enough volts to run the led strip correctly. I've been having really nice results with the led strips and I love the brightness.

The drawback is that I want to limit the volts to max of 12v and burn out the driver board.

**Rhyen Skytracker** · 06-20-2009, 08:28 PM

One of these should work, you use a resistor to determine the voltage output. I can't remember the exact resistance for 12 V but it should be on the back of the package. http://www.radioshack.com/product/in...01&tab=summary

EDIT: Here is the wiring schematic
http://www.datasheetcatalog.com/data...1/LM317T.shtml

**Onli-Won Kanomi** · 06-20-2009, 09:04 PM

Thats a nice find Rhyen...I'd pick up a couple of those myself except we don't have RadioShack here and they won't ship to Canada last I checked...but maybe somewhere else here has them so I'll have to look for them...thanks...

...another approach, which was my plan, but might work for Jase too, is to simply run down the batteries a little bit in other devices after each full charge and meter check them until they were at their safe voltage for Ultrasound saber use...not exactly an 'elegant' solution and of course that could only work using removable batteries in a holder not an in hilt rechargeable pack...

...but alas I havent had a chance to test it yet since I'm still waiting for my Ultrasounds to arrive though

...so meanwhile it's Corbin driver time for experimentation til then.