My first HV mod! But questions about 5v regulators.

[Billion]

It's just a box mod like everyone else's, but my first vape over 3.6v-4.2v. I first built a 14500 box mod (Nicostick) and although the batt life was waaay better, it was still basically the same vape.
For this new one, I used a 14500 and a NiMH cell for 4.8v. I know I cheated. But it's utterly amazing. Vapor, TH, flavor. All there like I've never experienced.
Now I want to do 2 14500's w/ a 5v regulator. I know everyone says the TI ones are the way to go, but I have one on hand from RS.

Question 1) Will the Rat shack regulator work (is it even worth using)?

Question 2) How do I hook it up? I searchbar'd but there's alot of tech jargin that I don't really understand. Take it easy, I'm not a ....., just not that electrically inclined.

Thank you everyone on the ECF for all the wonderful info that's been posted!
tobacco free for 15 straight days!

 

[mnealtx]

Do NOT mix battery types - you're risking a short.

 

[nick76]

Billion, read these thread at the bottom! For my tested experience, the RS regulator is L7805 is useless , i have 1 of those and 10 of other L7805 1.5A are in my junk box. I just got 5 UCC383TDKTTT-5 sample from TI, tested on my 2 18650 batts, the regulator got very hot . So i'm not gonna use those regulator. So I just ordered few other samples from TI and waiting to test :Plug-in Power Modules - Non-Isolated POL - PTR08060W - TI.com
and Plug-in Power Modules - Non-Isolated POL - PTN04050C - TI.com

http://www.e-cigarette-forum.com/forum/battery-mods/42186-picking-up-parts-here-there.html
http://www.e-cigarette-forum.com/forum/battery-mods/47666-5v-regulator-dc-booster-better.html
http://www.e-cigarette-forum.com/forum/battery-mods/34089-5v-regulator.html

Nick

 

[Billion]

Thanks for the info guys. I think I'm going to order up some TI samples.
In the meantime, if I try to use the RS 7805 regulator, will I destroy my batts trying to use it?
And Nick, aren't the regulators supposed to get hot? I don't know much about electronics but I remember reading it somewhere that it turns the excess voltage into heat.

Billion

 

[smonomo]

I installed my regulator on a 1/4" piece of wood to raise it up off the plastic, and absorb some of the heat. It also made it easier for me to solder.
http://www.e-cigarette-forum.com/forum/battery-mods/46986-my-first-mod-5volt-box.html

 

[boondongle]

The regulator does get hot, but not to a degree that I felt was dangerous. My regular atomizers get as hot from use.

The problem with the RS regulator is that it's not a low dropout regulator. I think you'd get a bit of use with the RS regulator, but it would stop working long before the batteries were low. I'm not an expert at this, of course.

 

[Billion]

The problem with the RS regulator is that it's not a low dropout regulator. I think you'd get a bit of use with the RS regulator, but it would stop working long before the batteries were low. I'm not an expert at this, of course.

When you say stop working before the batts were low do you mean the regulator will "shut down" and I can't vape or it will lose it's ability to regulate and all of a sudden I'm getting 7.2v to the atty.

Also, am I safe in assuming that the regulator should be wired up between the batts and the switch?

Sorry for all the questions guys, but I don't know how regulator failures will affect the device. I do have experience in other things that use batt packs but we never had to use regulators for anything.

 

[mnealtx]

When the dropout voltage is reached, the regulator stops passing voltage.

You can put it either between the battery and switch, or between the switch and atomizer. Most people choose the latter so that the regulator isn't constantly taking juice from the batteries.

 

[boondongle]

When you say stop working before the batts were low do you mean the regulator will "shut down" and I can't vape...

Yes. But I think I have the RS regulator confused with the one from SparkFun. That one has a 7v cut-off. If the RS one has a cutoff around 5v, it should work. I can't seem to find the minimum input voltage for the RS 7805 anywhere. Not an expert at all, though, so someone with more information should feel free to correct me if I'm wrong.

Also, am I safe in assuming that the regulator should be wired up between the batts and the switch?

No. It has three leads, and where you put it is important, or you can jump the switch, which makes the atomizer fire as soon as batteries are inserted. Wire it like this:

Red wire: Positive battery plate to switch; switch Vin on the regulator; Vout on the regulator to the center pin of the atomizer.
Black wire: Outer ring of the atomizer to the "on" lead of the safety switch.
Black wire: Ground on the voltage regulator to "on" lead of the safety switch.
Black wire: Center lead of the safety switch to the negative battery plate.

Make sure you don't connect the regulator in reverse, or it will probably fry.

 

[mnealtx]

7805 cuts off at 7v.

TI UCC 283-5 regulator cuts off at 5.5v.

You get more 'vape time' using the 283-5.

 

[Billion]

Well I hooked up the 7805, and it tastes like garbage. Any juice that I tried has a sort of flowery taste, hard to explain.
Based on what mneal just said, does it taste like junk cause it's @ 7v?!?
I only took 4 drags off of it with 4 different attys, 2 of which were clean. Lots of vapor but a wicked head rush.

No more testing for now...too...dizzy...

 

[mnealtx]

The regulator is only supplying 5v. Depending on your atty, you may get stronger flavor or a bit of a burnt taste, depending.

Make sure you give the atomizer a second to heat up before you start your drag (like a 'primer puff' on an auto battery).

 

[Billion]

I'm running the new style 901 attys. Not too sure I like the taste of 5v. I have some 510 attys and an adapter coming so I may try that out. But I'm not sure they'll be better. Back to the single cell box mod.
Thanks for all the help guys. Much appreciated!

 

[mnealtx]

Can't speak for the 901's as I've never tried them, but the 801's ROCK at 5v.

 

[Nuck]

I'm running the new style 901 attys. Not too sure I like the taste of 5v. I have some 510 attys and an adapter coming so I may try that out. But I'm not sure they'll be better. Back to the single cell box mod.
Thanks for all the help guys. Much appreciated!

I find that 5v is too high for a 901 (personal taste). I usually drop it down to 4.4-4.5 for a 901. You can do this by adding a resistor or a diode between the voltage out and your atomizer connection. It costs almost nothing and is easy to add.

The advantage over a regular 3.7 bat is that you will get a consistent 4.5v vape during the entire battery cycle.

 

[youngunner]

I just built a mod using a ti PTN0450CAM booster and it works awesome. At the time I only had 10440 3.7 360mAh bats to play with. Soooo It works awesome BUT the negative end of the battery spring instantly gets super hot- to the point where a 3 second hit turned the neg battery spring colors and started to melt the plastic battery box. Soooo- what does this mean? Is it the battery thats the problem? Why does the neg get so damn hot so quick?

 

[mnealtx]

You need more battery capacity - it's hitting the battery for a LOT more amperage than it can supply in a stable manner and it's overheating.

I'd recommend two AA size lithiums at a minimum, assuming you have the ripple capacitors in place as recommended in the datasheet for the 4050C. If not, I believe the recommendation is for an 18650.

 

[Nuck]

You need more battery capacity - it's hitting the battery for a LOT more amperage than it can supply in a stable manner and it's overheating.

I'd recommend two AA size lithiums at a minimum, assuming you have the ripple capacitors in place as recommended in the datasheet for the 4050C. If not, I believe the recommendation is for an 18650.

I tested a 18500 and 14650 and they both keep up fine with the caps. The 14500 seems to struggle.

Using a 10440 is just a really bad idea

 

[Billion]

So how big of a resistor am I needing to get to 4.5v? 1ohm?

 

[Nuck]

So how big of a resistor am I needing to get to 4.5v? 1ohm?

Depends on the atomizer resistance..but using 3.0 ohms as an average I'd get a 0.3 ohm resistor. A 1w resistor will be fine.