variable voltage circut

[cosmic charlie]

has anyone built this? does it work well for a pv mod? and do you have any pictures of the board, top and bottom?lElectronic Equiptment - DIY LM317 power supply

 

[Java_Az]

Lm317 is not stout enough for a VV mod. Some people have used them but they cut out fairly quick since they cant handle the amps. The LM323T is rated for 3 amps so it would be a better regulator to slap in the mod
LM323T STMicroelectronics Linear Regulators - Standard

Edit: sorry that would be a bad chip to use since the lm323t is a fixed 5 volts and not adjustable, but a adjustable rated for high amps would be a better choice

 

[WillyB]

The LM317 is unsuitable for our needs. The drop-out voltage is too high at over 2V, and "Guaranteed 1.5A output current" is too low.

 

[Jetmec]

Look through the mod threads for the Evercool by Bigblue great directions easy to build works great it is the only mod I use. and you can get the regulator from Texas Instruments for free just order the sample. the rest of the stuff and where you can get it is listed in the post.

 

[WillyB]

Look through the mod threads for the Evercool by Bigblue great directions easy to build works great it is the only mod I use.

How about much easier to build, very minumum soldering required, works just as well and no little parts sourcing and wondering if you got the right stuff.

http://www.e-cigarette-forum.com/fo...vv-mod-w-switching-regulator.html#post1886821

It's a winner.

 

[breaktru]

Yes WillyB. Switching Regulator is the way to go. Some are 85% - 96% efficient while the Linear Regulators like the one posted here is anywhere from 14%-40% efficient. Meaning battery drain.

 

[5cardstud]

This is the one I use and I've had excellent service with it. 3A Adjustable step down switching voltage regulatorI dropped it off the roof and knocked off the caps and the potentiometer. I got a new potentiometer and caps out of an old mobo and it's working great since that happened. It's a little costly though.

 

[cosmic charlie]

thanks for the response. Going to have to read more but I expected that. I'me trying to wrap my head around some of the theory, home alone and sick for the holiday too much cough syurp. Is basic diagram is sound the will protection diode help keep from blowing up a battery? with the output amps is it matching/exceeding the atty ohm resitance? this is much more complex than re-wireing my house.lol

 

[cosmic charlie]

well and the brightness of the led to judge the output sounded intreasting sorry if this is all covered somewhere

 

[cosmic charlie]

the dc-dc converter board looks like an easy out thanks. now if there was a dial or knob to seat on that adjustnment screw

 

[Para]

This is the one I use and I've had excellent service with it. 3A Adjustable step down switching voltage regulatorI dropped it off the roof and knocked off the caps and the potentiometer. I got a new potentiometer and caps out of an old mobo and it's working great since that happened. It's a little costly though.

5card, I used your chip in my Wood Box mod and it might be pricey, but it's a winner on performance. Thanks for suggesting it.

If you get a chance, how about reposting your box mod....it's one great looking wood box mod.

 

[WillyB]

This is the one I use and I've had excellent service with it. 3A Adjustable step down switching voltage regulatorI dropped it off the roof and knocked off the caps and the potentiometer. I got a new potentiometer and caps out of an old mobo and it's working great since that happened. It's a little costly though.

Well I would not call it expensive, it's a well designed complete solution... ready to rock. If you look at bigblue's guide there is some time, money, and careful soldering involved. And hopefully you get it right. Even if you only value your time at $10/hr yours is a better deal.

thanks for the response. Going to have to read more but I expected that. I'me trying to wrap my head around some of the theory,... Is basic diagram is sound the will protection diode help keep from blowing up a battery? with the output amps is it matching/exceeding the atty ohm resitance? this is much more complex than re-wireing my house.lol

I actually found that circuit intriguing and the PDF that went along with the kit explaining the reasoning for the diodes.

with the output amps is it matching/exceeding the atty ohm resitance?

Have no idea what you mean.

 

[cosmic charlie]

sorry I dont really know what I mean either... at least I'll admit it. It just seemed like a good place to start asking questions. are the diodes to protect surges/shorts from imput/output to power source? so a shorted atty wont kill the curcuit or cause a battery failure?

 

[breaktru]

Diodes protect back feeds. Allows current to flow in one direction.

 

[Java_Az]

sorry I dont really know what I mean either... at least I'll admit it. It just seemed like a good place to start asking questions. are the diodes to protect surges/shorts from imput/output to power source? so a shorted atty wont kill the curcuit or cause a battery failure?

Using protected batteries should keep them from exploding. Unprotected batteries are what you want to stay away from. IF you want to double protect them you can add a PTC Resettable Fuse to the circuit with a protected battery . They are basically like circuit breakers on a home panel once the rated amps are passed they open up so no voltage can pass. Once they cool down they will close letting voltage pass again. So there is no switch to flip they reset them selfs. I don't think i have seen anyone incorporate one in a mod but some battery pack makers slap them in the packs they make. They are also known as poly switches