mp2307 buck module aka KIS-3R33S Z with 2x 10440 in a 9v batt box mod

[nicotime]

Yep...TC...and it was cooool!! lol

You hit it right on the money Willy....at first I had a 1.6 coil hooked up on my breadboard...then because the little one was about ready to pop... I switched to a big ole 17 loop 2.9 coil I play with sometimes with 28ga wire. To be truthful it was not a real accurate kind of test...I was just doing different stuff and looking at numbers. I have a few more if this one is dead so I'll document what happens better next time.

 

[nicotime]

Ok...its still alive...I just took the popped cap off and put the same 22uf/10v back on....but I left the 24v power pack alone this time. Sorry about the video quality..didnt realize it was washed out so you couldnt see the one coil.



EDIT: Thanks to a great catch by WillyB...the info I stated on the video needs corrected.....the first coil was a .8 ohm coil..not 1.6 ohm. I grabbed the wrong coil when I redid the test thinking it was the same one...duh! The 1.6 ohm coil I used when the cap popped got so hot it melted the solder on the part that held spring tension on the wire so I mounted the...what I thought was the 1.6 ohm coil...in PCB connectors like the 2.9 ohm coil is.

Sorry bout that....I guess I was still traumatized by the firey cap!! lol

 

[asdaq]

Hey Nico, you OK? Better check for injuries, you seem to be losing some blood on the components:

http://i534.photobucket.com/albums/ee345/larryis3/Electronics/P1020756.jpg

 

[nicotime]

Oye...its just a flesh wound..LOL.....if it is its not mine...I scavenged that pot from my "what am I gonna do with this pile of junk" pile!

 

[WillyB]

Wow... cool test set-up.

 

[nicotime]

Thanks for the catch Willy...guys...see the update in the thread above with my video!

 

[jhonutz]

I use that IC,rebuild all in a custom PCB.It`s a very good switching regulator. Have some advantage this IC: small, work without external shottchy diode, IN/OUT small SMD capacitors.My PCB measure 20mm x 20mm

 

[zogu]

I ordered few weeks ago (before i saw this thread) kis modules and i hope that i will receive it this week. Now I don't have to think too much, everything is well explained, but i want it to work from 3.0 v to 6v fixed, that was plan because all vv on the net have voltage fixed like this. Maybe this is not important, but is it possible to put 2. zener diodes inside (on the pot ends to the ground?) and limit voltage that can't go lower and higher than desired values.
Thanks, best regards.

 

[WillyB]

...but i want it to work from 3.0 v to 6v fixed, that was plan because all vv on the net have voltage fixed like this. Maybe this is not important, but is it possible to put 2. zener diodes inside (on the pot ends to the ground?) and limit voltage that can't go lower and higher than desired values.

Of course it's possible, but actually 6V vaping is not really practical unless you use some big mAh cells. You always need more input voltage than your chosen output. For 6V that means more than 7V from your cells. Not a lot of vaping time there.

Here's the datasheet.

http://www.komputer.de/wordpress/wp-content/uploads/2011/10/MP2307_r1.9.pdf

There are formulas/tables for figuring voltages and they show an R1 and R2 resistor. You will probably want to figure what the board is using and proceed from there. You'll probably need another resistor + a trimmer, but getting it right can be tricky and you will need a breadboard to test for actual volts.

But you are right, having the vapeable voltage limits controlled by the trimmer is desirable.

One of the master modder's new mods left me cold. He tried to tout the 1V to whatever-the-cells-are-at voltage as an advantage over the Provari.

Hardly, what you end up with is a very twitchy to adjust mod with no real granularity for precise adjustments.

Maybe this will help explain.

As you can see not many degrees left to work with.

 

[zogu]

Thanks, I will play with board, whit resistor i'm sure that i can get desired values (one in series with pot and one in parallel to get required resistance, easier than finding pot), but i will also try with diodes.
I will post results here.
Biggest problem is box, i don't like fabricated aa boxes, i'm thinking to use some metal flashlight as a box.

 

[TomCatt]

Check this out. Plug-N-Play with KIS-3R33

eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

 

[WillyB]

Yea those have been around but I can't recall who built a mod with it.

The problem though, apart from the size, is the efficiency. It isn't using the MP2307 chip which appears to be much more efficient than those LM25XXs at the volts we actually vape at.

You saw my chart from the datasheet for the LM2596.

~75% is just barely better than a linear reg.

 

[TomCatt]

Yea those have been around but I can't recall who built a mod with it.

The problem though, apart from the size, is the efficiency. It isn't using the MP2307 chip which appears to be much more efficient than those LM25XXs at the volts we actually vape at.

You saw my chart from the datasheet for the LM2596.

~75% is just barely better than a linear reg.

Actually Willy, this module is a KIS-3R33 on a board with 'external' caps, pot and Vin/Vout connections. Similar to the LM2596 modules (which I'm vaping off of at the moment); but with a KIS not an LM2596 - at least that is what the picture shows


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[TomCatt]

I'll post some macro pics of mine when it shows up in a week or two


Sent from my iPod touch using Tapatalk

 

[WillyB]

Actually Willy, this module is a KIS-3R33 on a board with 'external' caps, pot and Vin/Vout connections. Similar to the LM2596 modules (which I'm vaping off of at the moment); but with a KIS not an LM2596 - at least that is what the picture shows

Just going by the listing.

DC-DC Step-Down Power Module 4A LM2596

 

[TomCatt]

Sorry for the big picture; but it's what eBay has:

Actual listing is:
"Kis-3r33 DC-DC Step-Down Power Module 4A LM2596 IN 4.75-24V TO 0.93V-18V"

They probably put the LM2596 in there since the LM2596 modules are relatively common on eBay and would generate more hits from searches.






ETA:
There is also a "DIY Kit" for this setup:
MP2307DN Kis-3r33 DC-DC step-down power module 4A (DIY Kit set) over LM2596 | eBay

 

[nicotime]

Ok...this thing is making me a bit paranoid now! This is the second cap I replaced after the first one went off like a tiny grenade! I had just hooked up the battery + and - and was reaching for the other wires to attach when it just exploded...no other wires were connected yet. This was the same setup I ran all the test with previously that I posted. The only thing I did different was I put my 18650 IMR on it forgetting it took two batts. Would an undervolt input do this? The only other thing I can think of is that tantalum caps will not work...does it have to be ceramic like it calls for?

 

[TomCatt]

Hmmm ... good question

I picked up a bunch of 22uF elecrolytic caps, didn't someone use these?
(to go with the 5 KIS-3R33S modules I got )

ETA:
Yeah, Nicks used 16V 22uF caps.

 

[nicotime]

DOH!! Now that I'm awake I just realized what happened...I normally run black wire for grounds...but on this one I used green because I didnt have any red at hand....so basically I had the batt reversed! I really need to stop playing when I'm half asleep...that and use only black and red wires for the + and - connections....that I understand no matter what...but when I do "green for ground"...my subconscious evidently still sees black as ground!

I know I know...look at the component not the wire color!!

@TC...I dont know if electrolytic caps will work...never tried it with this thing...but it specifically calls for ceramic caps. I'll have to get some ceramics on hand.

 

[TomCatt]

Nicksvap3 was saying he was using 16V 22uF caps. In his blog, he has a PT using 50V 22uF electrolytic caps (pictures) - http://www.e-cigarette-forum.com/forum/blogs/nicksvap3/1805-pt-smalls-vv-13-2v-kis-3r33s.html