Breaktru Forum
eCigarette Forum => Modding => Topic started by: Breaktru on May 16, 2012, 02:50:32 PM
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Para from ECF gave my name to Brandon from Evolv to try out their new DNA module in a mod. Thanks very much Para.
These are preliminary tests of the new Evolv DNA 12 module.
Testing right now with (2) paralleled 18650 Trustfires but will later use (2) Li-Po 20c batteries.
The Trustfires are under rated for the DNA as you can see by the Battery Level readings. Voltage drops from 4.17v to 3.27v Definitely need higher "C" rating batteries as per DNA spec sheet.
Battery update: Using my Li-Po's on it and it only dropped Four Hundreds of a volt (0.04v) on battery input.
I have found that the Voltage, Amperage and Wattage readings fluctuate considerably while holding down the fire button.
I have coded to calculate V, A and Watts every 1000ms (1second).
With two 20c Li-Pos in parallel, the highest wattage achieved is 10.68 watts. Starts at 9.68 watts and fluctuates to values in between to max of 10.68.
With one 20c I get slightly lower max of 10.02 watts.
Update on wattage: On occasion I get over 11 watts. I've gotten 11.58watts but I can not achieve it every time. It is NOT consistent.
Update II: I was using the beta test model. A newer version has been released that can achieve 12 watts.
As per datasheet 3.3 ohms should get you 12 watts but I tried a 3.3 ohm atty and only get 9.7 watts.
I also notice that it was a pulsed output. I can hear the atty pulsing on and off.
This is weird: Wanted to see if I see a red err LED on the DNA so I tried the 3.3 ohm atty again and got NO pulsing and get 10.38 watts. Still fluctuating readings. NO red LED indicating.
Fluctuation is pretty wide in range and can vary from a tenth of a watt to as much as over a watt.
I understand that VW maintains wattage with the load. Resistance of atty may vary and the DNA adjusts accordingly to maintain the set wattage. But........ Wattage readings should NOT fluctuate.
Also most of my testing is with a fixed load. A Ceramic 20 watt resistor. No resistance variation should occur.
Right now my highest wattage is 10.68w. Mamu and BigFran was able to get 11w by shorting up on the battery wires.
Sometimes that is not practical when using a particular enclosure due to the placement of batteries. My batteries are soldered so batt contacts is not an issue. I am using 20ga wires on power connections.
I'm not concerned with getting more wattage. I like tasting my juice and not sizzle it. With the juice I'm using, anything over 7watts is harsh and tastes burnt.
(http://breaktru.com/ecig/dna_mcu1.jpg)
(http://breaktru.com/ecig/dna_build1.jpg)(http://breaktru.com/ecig/dna_build2.jpg)
(http://breaktru.com/ecig/dna_build3.jpg)
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Holy crap batman. That is amazing for a novice like me.
Well done breaktru :rockin smiley:
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Fantastic work breaktru, well done :beer-toast:
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Well done my man!
It makes NO sense to put that DNA unit in a mod without a display, or am I missing something.
What you did with the display, IMHO is what the DNA was intended to be used with. Some sort of display. What would be the point of guessing the wattage output?
:thumbsup:
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See updates to original post............
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Looking at your comment about the wattage fluctuation, I agree that a variable wattage unit should not fluctuate wattage.
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How would one connect two DNAs for 24 watts like Brandon stated in the video?
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How would one connect two DNAs for 24 watts like Brandon stated in the video?
I'm assuming you would parallel all the pins. Is it worth it? I got mine for free but would I spend $35 or $70 for two.... NO
I would buy a 30watt board for a lot less. Like the 08100w or OKR-T/10.
All this hype on Variable Wattage as being the BEST, in my opinion is overrated. Yeah but you can swap attys without readjusting wattage.
So what. If you are using a Display that reads wattage, what's the big deal to readjust. How often do you do that?
In 0.2 seconds I can readjust.
Maybe a V.W. is useful if you DON'T have a display but with one, you can see the wattage.
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Excellent point, D! :yes"
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Fully agree with that. Why pay $70 for something you can get for a tenth that with the only requirement you manually adjust instead of automatically.
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Fully agree with that. Why pay $70 for something you can get for a tenth that with the only requirement you manually adjust instead of automatically.
Yup. if you have wattage displayed, what's the big deal adjusting it? Well... got it for nothing so I went with it.
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I like the second black one better. I scrapped the first box.
(http://breaktru.com/ecig/dna_mod01.jpg)(http://breaktru.com/smf/index.php?action=dlattach;topic=588.0;attach=1591;image)
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Dave- curious if you know (otherwise I'll ask Evolve).. I assume that the charger connections on the module simply tie into the battery connections and require an 'intellegent' charger (ie there is NO charging chip/circuit on the module itself)?
And I guess I have a different take on using a watt controller vs a voltage controller. I don't really care what a dial (or a display) says because I'm going to change it according to my juice & mood anyway. Having a circuit that gives me the additional benefit of not needing to tweak it too much when I grab a different carto and (hopefully) keeps my desired vape preference for a wider range of other variables is well worth $36.50 plus batts, box, & hardware, imo. In theory.
I'll find out soon enough though, as my chip came in the mail today! :thumbsup:
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Can't wait to see your build.
I asked Brandon over at Evolv the other day what the advantage of the Charger Pins where compared to just hooking it up to the battery and he replied back that it is the same connection. Just the convenience of a spot to hook on to.
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If I didn't use the li-po's I would have been able to get this in a much smaller box. But the 20's are nice to have. The display looks lost on the front panel.
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Can't wait to see your build.
I asked Brandon over at Evolv the other day what the advantage of the Charger Pins where compared to just hooking it up to the battery and he replied back that it is the same connection. Just the convenience of a spot to hook on to.
Thanx for the info. I had a feeling you'd asked already.
I don't think my build will be very interesting.. thinking of seeing how much batt I can stuff into a Revolution V2 case that I changed over to 808D. Probably close off the open squeeze bottle hole, see if I can put the pot where the 'ufo' lights are currently.
Sitting here typing, I'm thinking maybe I can make 3 little decals for the pot ... :) .. :laughing: .. :laughing2:
and then just use the other 3 existing V2 leds for the batt indicator.
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For those of you who do not know what the DNA is, here is a video of the creator talking about it.
GO TO Timeline 0:49:50 for the start of the interview: http://youtu.be/klsEJj5I1zY?t=49m50s (http://youtu.be/klsEJj5I1zY?t=49m50s)
http://youtu.be/klsEJj5I1zY?t=49m50s (http://www.youtube.com/watch?v=klsEJj5I1zY&hd=1)
http://youtu.be/klsEJj5I1zY?t=49m50s
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So let me ask you, what do you think of it?
I like the fact you can stack boards for more power :thumbsup:
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So let me ask you, what do you think of it?
I like the fact you can stack boards for more power :thumbsup:
I think maybe what I stated in Reply #7 will help
http://breaktru.com/smf/index.php/topic,588.msg3770.html?PHPSESSID=9089794cedd9b17e28410a72e3cc526a#msg3770
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Dang it I over looked that whole part of the post and dont know why :wallbash:, I read everything else. :facepalm:
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Can't wait to see your build.
I asked Brandon over at Evolv the other day what the advantage of the Charger Pins where compared to just hooking it up to the battery and he replied back that it is the same connection. Just the convenience of a spot to hook on to.
I found a disadvantage to using the charge pins on the DNA, at least on my setup.
By using the pins, the circuitry is live. I don't want to use diodes to block the reverse feed so I chose to break the charger negative side to the on/off 3rd pin of the on/off switch.
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With the right camera distance the display looks pretty clear:
(http://breaktru.com/ecig/mcu_dna_display2.jpg)
Not so clear but over 11 watts. Max was 11.58 watts.
(http://breaktru.com/ecig/mcu_dna11w.jpg)
USB charging:
(http://breaktru.com/ecig/mcu_dna_charge.jpg)
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Just tree words - It is amazing!
So close to the absolute perfection.
Now we just need undestructable atomizer ;)
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Magnificent mod ;hubba; Now that's a lot of mod for a gal. But I can handle it.... I think. :laughing2:
You can send that to me and I'll test it out for ya :yes"
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USB charging:
(http://breaktru.com/ecig/mcu_dna_charge.jpg)
Did you use the same USB charger that you used in your first microcontroller mod?
And how did you get the red LED to display on the outside? :Thinking:
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Did you use the same USB charger that you used in your first microcontroller mod?
And how did you get the red LED to display on the outside? :Thinking:
Yes I did. Same charger except this is a mini USB port and the other was a micro USB port. I put a length of clear 0.80 monofiliment line over the on-board smd LED and poked it thru a drilled hole to see it.
Like a Fiber Optic type effect. The LED is actually about an inch away or more from the outside hole. Worked out great.
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Yes I did. Same charger except this is a mini USB port and the other was a micro USB port. I put a length of clear 0.80 monofiliment line over the on-board smd LED and poked it thru a drilled hole to see it.
Like a Fiber Optic type effect. The LED is actually about an inch away or more from the outside hole. Worked out great.
I would love so much to be able to build something like this. If only you could put out a kit, I would be thrilled to death.
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How cool would that be, a mcu mod kit or a circuit board with a wiring diagram... :applaude:
I have been following your mods breaktru and as always love this one as well.
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Can't wait to see your build.
I asked Brandon over at Evolv the other day what the advantage of the Charger Pins where compared to just hooking it up to the battery and he replied back that it is the same connection. Just the convenience of a spot to hook on to.
I was wondering about the charger pins. thanks for the explanation. I thought it had a charging circuit built in but now I know better.
I was thinking about using maybe a 1 amp charger for a faster charge instead of a 500ma one.
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I picked up a couple of chargers on ebay that has to be hacked by changing a resistor for a 1 amp charge rate. See datasheet: http://www.google.com/url?sa=t&rct=j&q=tp4056&source=web&cd=1&ved=0CFIQFjAA&url=http%3A%2F%2Fwww.vitexic.com%2Fdata%2FTP4056Eng.pdf&ei=_KrLT-z8PMbF6gGmvd3uDw&usg=AFQjCNEJoISKgFcJsFKPmoNKxSCITp8DcA&cad=rja (http://www.google.com/url?sa=t&rct=j&q=tp4056&source=web&cd=1&ved=0CFIQFjAA&url=http%3A%2F%2Fwww.vitexic.com%2Fdata%2FTP4056Eng.pdf&ei=_KrLT-z8PMbF6gGmvd3uDw&usg=AFQjCNEJoISKgFcJsFKPmoNKxSCITp8DcA&cad=rja)
I kinda like my 500ma because it is a smarter charger. See datasheet: http://www.sparkfun.com/datasheets/Prototyping/Batteries/MCP73831T.pdf (http://www.sparkfun.com/datasheets/Prototyping/Batteries/MCP73831T.pdf)
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Isn't the 500mA charge current optimal fast charge for Li cells ? Above that is posible (1C-2C) but this will shorten life of the battery?
I know golden rule - slow charge => slow discharge => long live :)
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Isn't the 500mA charge current optimal fast charge for Li cells ? Above that is posible (1C-2C) but this will shorten life of the battery?
I know golden rule - slow charge => slow discharge => long live :)
I don't think 1 amp charge rate would hurt even for a single batt. I'm using 2x Li-Po batteries and that would be 500mah per cell.
The charger is made for Li-ion and Li-po batteries w/ output of 4.2v and the charge current can be selected by changing the resistor as follows:
Rprog Current Setting
RPROG - IBAT
(k) - (mA)
10 130
5 250
4 300
3 400
2 580
1.66 690
1.5 780
1.33 900
1.2 1000
The charge voltage is fixed at 4.2V, and the charge current can be programmed externally with a single resistor. The
TP4056 automatically terminates the charge cycle when the charge current drops to 1/10th the
programmed value after the final float voltage is reached.
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very impressive. good work. I would love to own one just like this mod ;hubba;
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I've gone through several charging cycles now and have found that two parallel 1000mah, 20c li-pos take exactly 4 ½ hours to fully charge with the 500ma charger.
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And how long they last in vaping (according your style of vape of course)
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And how long they last in vaping (according your style of vape of course)
They go from 4.17v (100%) to 3.20v (0%) in 2½ to 3 days.
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WoW it's amazing live time for vaping :rockin smiley: :beer-toast:
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hey break,
do you know if i can use this charger:
http://www.sparkfun.com/products/10401
with this battery, 3.7V 1200mAh 20C Lipo Li-polymer:
http://www.ebay.com/itm/320892649444?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
wondering if i can use the charger without any modding with the single cell above using the dna charging terminals?
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hey break,
do you know if i can use this charger:
http://www.sparkfun.com/products/10401
with this battery, 3.7V 1200mAh 20C Lipo Li-polymer:
http://www.ebay.com/itm/320892649444?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649
wondering if i can use the charger without any modding with the single cell above using the dna charging terminals?
Yes. that is the same charger I'm using.
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thanks so much man. thought so and had ordered 3 of each (batteries and chargers) but wanted to make sure.
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should i go battery out to battery in on dna and charger board out to charger in on dna?
would there be a different or better setup like going battery out to charger board and then charger board to battery or charger in on dna? will it work as a passthrough in any scenario?
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should i go battery out to battery in on dna and charger board out to charger in on dna?
would there be a different or better setup like going battery out to charger board and then charger board to battery or charger in on dna? will it work as a passthrough in any scenario?
For convenience I went battery to DNA battery terminals and charger to DNA charger terminals.
According to Brandon, the the Charger terminals on the DNA is the same as the battery terminals.
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will it work as a passthrough in any scenario?
The charger puts out 500ma so if your battery is low, a half amp is not going to power an atty. If you have some life in the battery you should be able to vape as the battery will supply the needed amperage.
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very cool...amazing info. so if i decide to go battery out to charger board in and charger board out to battery in on dna it should work just the same?
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very cool...amazing info. so if i decide to go battery out to charger board in and charger board out to battery in on dna it should work just the same?
There is NO IN connection on the charger board. The technical IN is the USB jack connection. The (+) and (-) points are the same as the battery jack on the charger so you can connect straight to the battery and there is NO need to connect the charger to the DNA at all.
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this is what i meant:
(http://i1124.photobucket.com/albums/l561/jphotobuckets/dna_charge.jpg)
sorry for being thick...:)
ok, or no?
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this is what i meant:
sorry for being thick...:)
ok, or no?
OK, Yes
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Soon Evolv will start selling a USB charging module for their DNA.
I received two Micro USB charger boards a couple of days ago from Brandon for testing.
Nice and tiny. I don't have the spec's on it but I am thinking it maybe 500mah.
Here is a size comparison with the two others I have used.
(http://breaktru.com/ecig/dna_charger1.jpg)(http://breaktru.com/ecig/dna_charger2.jpg)
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In the photos above, the red USB charger (500mah) takes 2 hours to charge a single 20C, 1000mah Li-Po.
Using the Evolv DNA charger I pulled the battery off after 5 hours. Red charging light remained lit. The battery started out at 3.4v and after 5 hrs measured 3.8v. Fully charged, this battery usually measures 4.17v
During charging I measured the amperage rate at 0.8uA (micro amps). This is suppose to be a 500mah charger according to the DNA datasheet.
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Sounds like you got a dud.
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Same result with the second charger on Li-Po that Brandon sent.
I thought that maybe these chargers couldn't handle a Li-Po so I discharged an 18350, 1200mah, Ultrafire (blue) to 3.38v and put it on charge monitoring Voltage and amperage.
Charging rate is the same 0.8uA. Voltage slowly increased from 3.43 and slowly climbing. It's on charge now for 1/2hr and has reached 3.65v and still charging at 0.8uA. After 3 1/2 hrs it's at 3.86v.
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Okay, I sent Brandon a PM yesterday and he just replied.
He sent me the wrong chargers.
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Okay, I sent Brandon a PM yesterday and he just replied.
He sent me the wrong chargers.
Oh boy. Hope he waits for your testing before making them available to the public.
Sounds like what happened with the first version of the DNA not being able to reach 12w max
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Okay, I sent Brandon a PM yesterday and he just replied.
He sent me the wrong chargers.
I have the new chargers that Brandon sent and they work well. These are the same exact size and look exactly like the previous ones he sent.
Charging rate is 500mah, actually started at 520mah and slowly declined to Zero when charging was complete.
Red light while charging and and a Green light when completed. Great small size. You can squeeze these in almost anywhere.
Took 2hrs 15min for a 1000mah 20C battery to completely charge.
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Just stumbled on to this forum as I have been starting my own mods, BreakTru and CraigHB you both do fantastic work and the discussions here are an invaluable resource. I'm planning two mods, one based on the DNA and eventually a more complicated mod using something like a TI4050 with a control circuit and the needed safety monitoring. The DNA is attractive as a first project as it contains the safety monitoring and simple setup so I can get the sensing circuits and display dialed in before taking on a more complicated project.
What have you found to be the best way to get an accurate current measurement? Hall effect sensors or are you measuring the voltage drop across a small resistor in series with the load and driving that to the ADC with an op-amp? Thanks!
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Just stumbled on to this forum as I have been starting my own mods, BreakTru and CraigHB you both do fantastic work and the discussions here are an invaluable resource. I'm planning two mods, one based on the DNA and eventually a more complicated mod using something like a TI4050 with a control circuit and the needed safety monitoring. The DNA is attractive as a first project as it contains the safety monitoring and simple setup so I can get the sensing circuits and display dialed in before taking on a more complicated project.
What have you found to be the best way to get an accurate current measurement? Hall effect sensors or are you measuring the voltage drop across a small resistor in series with the load and driving that to the ADC with an op-amp? Thanks!
Hey Synchro, welcome to the forum. Glad you found us.
I take the easy approach with a hall effect sensor. I believe Craig builds his own which I assume is the resistor/op-amp method.
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Thanks! Do you mind if I ask what sensor you are using?
I've been looking at this part (http://www.digikey.com/product-detail/en/ACS711ELCTR-12AB-T/620-1370-1-ND/2470594) since I'm using the 3.3 mini board and dont want to put a 5v reg in to keep it small and the component count down. Like that it has an overcurrent latch as well, could be useful later on. Wish it was through hole but that can be overcome.
Love that OLED display you are using, has a lot of advantages for modding being small and clear.
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I use a current sense resistor and an op-amp. The current sense resistor is 10m Ohms and the op-amp is set up as a differential amplifier with a gain of around 50.
I would recommend the chip Dave uses for the simplicity.
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Thanks! Do you mind if I ask what sensor you are using?
I've been looking at this part (http://www.digikey.com/product-detail/en/ACS711ELCTR-12AB-T/620-1370-1-ND/2470594) since I'm using the 3.3 mini board and dont want to put a 5v reg in to keep it small and the component count down. Like that it has an overcurrent latch as well, could be useful later on. Wish it was through hole but that can be overcome.
Love that OLED display you are using, has a lot of advantages for modding being small and clear.
I use the ACS712 which is 5v, 5amp.
I just want to point out that the display in very tiny. Hope you have good eyes... :laughing:
The text is very sharp and crisp and doesn't need a backlight. Text is illuminated
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Can i ask what micro controller you use with the dna? Im planning to build one myself but im still studying about it. Thanks man im really inspired!
Oh im sorry its already been mentioned.
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Man, you weren't kidding...that display is tiny. Its really sharp and clear though, and its kinda fun to play with bitmaps on the oled and animate them. :D I think next time I would go for the 128x64 so I can use a bigger font. One thing I'm gonna try is to see if a digital pin on the controller will power it. The current draw is low enough and it would be nice to turn the display off when idle with a simple digitalpin low command.
Had a good weekend, got the display wired up, voltage dividers made and tested, most of the code done which I'm sure I'll need to tweak once everything is together. Still waiting on the Lipos to arrive but at least they are (somewhere) in the US now.
One thing I've been reading alot about is using the measured Vcc from the controller for more accurate measurements instead of just assuming 3.3v in my case which makes sense to me...(Count/1023)*Vcc. Is this a common practice and worth the extra code for the increase in accuracy? I'm curious if just once when the controller is started is enough or measuring the Vcc constantly is needed as regulators will drift with temp, batt, etc.
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The LCD is load is heavily capacitive since it uses a charge pump to drive the display. It's generally a bad idea to power a capacitive load directly from a digital I/O pin. It's because the inrush current causes a large drop in voltage within the MCU and can cause indeterminate behavior such as spurious resets and locks. To control loads like this, you should use an analog switch or a complimentary MOSFET pair.
Your ADC is only going to be as accurate as your voltage reference. If you are using Vcc as a reference, you want to use a precision LDO regulator to minimize error. Commonly they are available with 2% accuracy and they can be found as low as 0.5%. Some MCU's have a built-in voltage reference module that is highly accurate. If the MCU has one, it's always better to use that than Vcc. If the MCU does not have an internal voltage reference, you can use a voltage reference chip to provide one.
Accuracy always boils down to what you're willing to pay in cost of components and complexity of design. I wouldn't go to overboard with it. It's only an e-cig and if you can keep error under a couple percent, that's more than adequate.
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Thanks Craig, sounded like an easy display on/off but I won't mess with it if it causes other problems. Not that big of a deal to leave the oled on until the MCU goes into sleep mode.
Interesting, my mcu is based on the ATmega328 running at 8MHz which has a 1.1v internal reference which I've found to typically be around .9v The onboard 3.3v regulator is pretty tight and analog measurements of Vcc are typically pretty close to my DMM. I'll have to experiment with both, more to learn than anything else.
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I'm not a familiar with the ATmega328, but the ADC module should have configuration bits that allow you to select a range of references. All MCU's allow you to select select Vcc or external input for V+ and Vss or external input for V-. Ones with internal voltage references should provide a set of values you can assign to V+ and V- as well. I don't know for sure though, maybe that MCU only provides one value for the internal voltage reference. That would be kind of weak though.
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Well, a little google fu and some trial and error and my readings are spot on. Hardware Hacking has a good tutorial on using the reference voltage and normalizing the DAC, had to fiddle a bit to get it but when using a AA battery to test it was spot on to the DMM. Thanks again Craig and BT. This has been a fun project, my degree is computer eng but my profession is software modeling power systems and I never get to do any hands on anymore.
Everything is ready to go now, just waiting on batteries. Had a really nice case that would just barely fit everything and I cracked it while drilling for the 510 connection. Ugh. Have another one that will do but it is big.
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batteries arrived today, got everything together and tested. Voltages are dead on, but current needs some work. Will take a bit to get the ratio correct. Almost there...
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Looking good there boss :)
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Very good Synchro. Well done my friend. Welcome to the club..
I see you have the latest DNA release and achieved over 12 watts.
Do your readings fluctuate any?
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Thanks guys, been fun and frustrating at the same time. The help from the two of you is greatly appreciated! Still nowhere close to being done, but at least I can use it at this point.
Not seeing much fluctuation at all. Pretty impressive actually, gets pretty close to 13W which is cool although around 10.5 is where I like it. The 20C cell makes a difference as well, the DNA wasn't as strong with an IMR I tested it with earlier. Its big tho, much bigger than I intended. I'd really like this to fit inside a 4.5x2.2x1 box I have coming, and couldn't do that right now. I think the next step is to look into the ATmega chip you are using BT so I can consolidate the bulk of the circuitry onto 1 board that runs over the length and width of the battery. I haven't built a lot of mods tho, so i'll get better as I go. Having gone through it once now, I'll pick better suited components and plan it out better. I knew this first one was going to be more of a test run than anything else.
Its on a charge now, 500mA takes forever. Funny that the first charge is always nerve wracking.
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Cool sync :rockin smiley: congrats on your build. It's nice to see all the info on one screen like Craig and breaktru.
I expect to see more mods coming with an LCD or oLed display
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Yes, that's what's convenient about the LiPo flat cells. They fit nicely under a PCB. Perfect for a box mod.
You can charge your cell quickly with a DC benchtop power supply. The 20C 2200mAh cell can handle 2C or 4.4A when charging. Just set your DC power supply to 4.2V and limit current to 4.4A. The cell will charge in a half hour. I do it routinely on the one cell I use all the time for testing. I've beat the hell out of that one cell and it's still got most of its original charge capacity.
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batteries arrived today, got everything together and tested. Voltages are dead on, but current needs some work. Will take a bit to get the ratio correct. Almost there...
Way to go synchro. Excellent work
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Hmmm...dont have a DC supply here, but I think this usb charge breakout board can be modified to 1 amp. I think BreakTru did this so I'll see if I can find where he found out how, that would be better at least.
Got it all boxed up and (still) charging, vapes pretty nicely. Ranges between 6 and 12.5 watts which is plenty for me.
My PTN4050C samples are calling my name now....did someone say digital pot?
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Hmmm...dont have a DC supply here, but I think this usb charge breakout board can be modified to 1 amp. I think BreakTru did this so I'll see if I can find where he found out how, that would be better at least.
Got it all boxed up and (still) charging, vapes pretty nicely. Ranges between 6 and 12.5 watts which is plenty for me.
My PTN4050C samples are calling my name now....did someone say digital pot?
Looks real nice. Hell yeah.
Which charger did you use?
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Thanks sir! Not too bad I guess, I did not do great at modding the case - hence the electrical tape. I do have these two cases coming in a week or two that I'll plan a little better and do a nicer job:
http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=380335740247&ssPageName=ADME:L:OU:US:3160 (http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=380335740247&ssPageName=ADME:L:OU:US:3160)
http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=330357824336&ssPageName=ADME:L:OU:US:3160 (http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=330357824336&ssPageName=ADME:L:OU:US:3160)
This is the charge board:
https://www.sparkfun.com/products/10401
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One of these (http://www.mastechpowersupply.com/dc-power-supply/linear-power-supply/volteq-regulated-variable-dc-power-supply-hy1503d-15v-3a/prod_64.html) DC power supplies will do most of what you need to do and it's cheap enough. Their full range of linear DC power supplies is here (http://www.mastechpowersupply.com/variable-power-supply/linear-power-supply/cat_6.html).
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Thanks sir! Not too bad I guess, I did not do great at modding the case - hence the electrical tape. I do have these two cases coming in a week or two that I'll plan a little better and do a nicer job:
http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=380335740247&ssPageName=ADME:L:OU:US:3160 (http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=380335740247&ssPageName=ADME:L:OU:US:3160)
http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=330357824336&ssPageName=ADME:L:OU:US:3160 (http://www.ebay.com/itm/ws/eBayISAPI.dll?ViewItem&item=330357824336&ssPageName=ADME:L:OU:US:3160)
This is the charge board:
https://www.sparkfun.com/products/10401
Didn't notice the tape.
This charger is set to 500mah. See photos attached for 1amp:
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Nice, thanks BT!
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Great job.
Thank you very much for sharing. People like I used a lot of help. :applaude:
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You wont' be able to get a 1 Amp rate out of that chip. It will overheat and go into thermal limiting. I know because I tried already. You have to use the MCP73833 with the thermal pad on the bottom and it has to be soldered to a ground plane to act as a heat sink. I've seen MCP73833 modules available from Adafruit.
The other option is to use a charger module that utilizes a switching regulator, they don't generate any notable heat, but they tend to be too bulky for an e-cig mod.
Yet another option is to simply use a charging connector in the mod with the charger electronics external to the device. That's a good solution for dual series cells.
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Well it sound good looking at the Charger datasheet formula.
Nothing like real live testing
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Well, you might be able to milk it for a little more. Just put an ammeter on the input with a 1k rate resistor. Take note of the most current it will draw (there's very little overhead). Highest heat occurs at lowest battery voltage. Select a resistor for a charging rate just below its maximum.
I found its max rate before, but it was some ago and I dont' remember at all what it was. I only remember it couldn't do a 1A rate.
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Hmmm...changed the resistor this weekend and it didn't seem to complain although I didnt watch it that close. Charge time was reduced although without any timing or calculations to back that up. The AC charger I use is .8A so maybe it just sneaks under from throwing it into thermal limit (or I just wasnt paying enough attention to notice) 8). Will look into that circuit, thanks for the tip Craig!
Taking the DNA out to put in a simpler mod this weekend, just the DNA and an LED voltage display with a 3 way switch so I can see either atty or battery voltage.
Going to start breadboarding the next one, TI 4050C mod. Not sure where I want to go with this one, but not in any hurry. Was hoping to get some time to look into digital pots this weekend more than I did, seems like SPI is popular for interfacing them which may interfere with the interface for the OLED.
Also, been thinking about incorporating a low voltage cutout as well to protect the battery. Simple enough to use a shunt reg diode and resistor for voltage detection, what to do with it from there I haven't figured out yet. Could just drive a warning LED or to drive a logic high signaling the MCU to sleep but I'd like to cut out functionality altogether ensuring the battery can't go below the threshold.
Just ideas I'm pondering but haven't had time to research yet. My daughter made the Varsity volleyball team so much of my free time is shuttling teenage girls to and from practice.
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Hmmm...changed the resistor this weekend and it didn't seem to complain although I didnt watch it that close. Charge time was reduced although without any timing or calculations to back that up. The AC charger I use is .8A so maybe it just sneaks under from throwing it into thermal limit (or I just wasnt paying enough attention to notice) 8). Will look into that circuit, thanks for the tip Craig!
I'm curious to find out what amperage it is actually charging at. Can you place an amp meter between battery and charger leg?
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Sure, I'll do that when I open it up to move the DNA to another mod.
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If you select a 1k resistor, the rate will end up being regulated by the controllers built-in thermal limiting. When the battery is low and the differential between input and output is highest, current will be lowest. As battery voltage climbs, the chip will run cooler and may even hit the 1A rate for a time.
So, you'll see a reduction in charging time for sure, but I don't know, it's probably not a good idea to rely on the chip's thermal protection. Better to set it to a rate you know it can handle.
That's the booster, right? For a low voltage cut-out without an MCU, use a voltage detector and MOSFET. If using an MCU, drive the LDO regulator's enable pin with a voltage detector. If things are designed right, current draw well under a micro-Amp can be acheived. My mod draws 250 nano-Amps when the low battery cut-out engages at 3.0 Volts. Though that's a backup safety feature. The MCU detects a low battery 3.3 Volts open circuit. I was using 3.5V open circuit before, but recently changed it after I decided I wanted to milk the extra 50mAh out of it.
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I just re-read the datasheet for the charger and found this:
Programmable Charge Current: 15 mA to 500 mA
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Oh yea, I might be wrong about all that, oops. I was messing with an MCP73833 in an MSOP package as opposed to the DFN package. Both are programmable to 1 Amp, but only the DFN package has the thermal pad so only the DFN package can handle the 1A rate.
It may be possible the 73831 will not go over 500mA regardless of the rate resistor. On the other hand, that spec might just reflect what it's rated for. Someone will have to put an ammeter on one with a 1k rate resistor to say for sure.
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Looking at the datasheet for the 73831, its a CC/CV type charge circuit and I wonder if trying to boost the current will throw off the algorithm. It also says that charging at 500mA is "Not production tested. Ensured by design."
Adafruit has the MCP73833 modules but they look to be a bit bigger as it has 2 jst connections. Default is 500mA but is adjustable to 1amp with a 1K thru-hole resistor and can also use a thermistor for temp monitoring during the charge.
https://www.adafruit.com/products/259
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Looking at the datasheet for the 73831, its a CC/CV type charge circuit and I wonder if trying to boost the current will throw off the algorithm. It also says that charging at 500mA is "Not production tested. Ensured by design."
Adafruit has the MCP73833 modules but they look to be a bit bigger as it has 2 jst connections. Default is 500mA but is adjustable to 1amp with a 1K thru-hole resistor and can also use a thermistor for temp monitoring during the charge.
https://www.adafruit.com/products/259
I've use this one at 1 amp for my MCU Nokia mod: http://goo.gl/07sWv (http://goo.gl/07sWv)
but since replaced it w/ a 500mah DNA charger that is much smaller due to space confinement.
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The evolv charger is small, what IC does it use? I like the one from Spark as it uses the CC/CV charge cycle which is supposed to be better for preserving the longevity of the batteries (like a Pila charger for IMR's).
Craig, something like the NCP/NCV300 series from On Semi? Those seem very accurate, low Q current and manage hysteresis well. Would that be sufficient to drive the gate of a P-channel mosfet without a lot of extra components?
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Yes, those are the voltage detectors I use, NCP300 (http://www.onsemi.com/PowerSolutions/product.do?id=NCP300). One can drive a MOSFET no problem. For a 3V cut-out, you'd want to use a NCP300LSN30T1G with an N-Channel or a NCP300HSN30T1G with a P-Channel. Don't use a pull-up or pull-down on the MOSFET gate or regulator enable pin othwise you may get additional active draw.
The data sheet indicates 250nA active draw, but I'm getting less than that, 150nA. I get 250nA total when active with leakage from the rest of the circuit as measured by my Extech MM570A meter. It's a top-of-the-line meter with the resolution and accuracy to measure currents that small.
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The evolv charger is small, what IC does it use? I like the one from Spark as it uses the CC/CV charge cycle which is supposed to be better for preserving the longevity of the batteries (like a Pila charger for IMR's).
I have 4 of the evolv chargers and each one has a different number on the chip. Must be evolv's ref number. Google returns nada on the the number.
I've used the Sparkfun's charger on my first USB and commented about it's Pre-Conditioning feature.
I was thinking about cutting it down in length by cutting the board just above the (+) and (-) wire holes, removing the top portion w/ the JST connector.
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I was thinking the same thing BT since I don't use the connector, just lop off the top above the two thru hole connections to save space. Preserves the mounting hole as well.
I've kinda hijacked your thread here BT, sorry about that. I'll start a new one for the next mod.
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Taking the DNA out to put in a simpler mod this weekend, just the DNA and an LED voltage display with a 3 way switch so I can see either atty or battery voltage.
I'm thinking about doing the same thing. Im planning to use a 3way switch but im thinking i might damage the dna cause the negative for Vin and Vout are seperated. Is it ok if we wire it altogether with the negative wire from the display?
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I'm thinking about doing the same thing. Im planning to use a 3way switch but im thinking i might damage the dna cause the negative for Vin and Vout are separated. Is it ok if we wire it altogether with the negative wire from the display?
Not having the actual schematic for the DNA and that a member tied the negatives together and damaged the DNA, I would stick to the DNA wiring spec's.
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Is there a way we could use the display to show battery charge and atty?
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I hadn't heard that about the DNA being damaged by joining the negatives from the in and out. The switch I bought from digikey has 6 terminals, in this case both pos and neg for atty, battery and display. It's a 3 position switch so I plan on having it wired in a atty - off - battery configuration and the negs for battery and atty won't be connected through the switch at all. The display is just a 3 digit voltage display I got from Madvapes. Should be easy enough.
Here's the switch, DPDT on-off-on: bit.ly/P0xhDN (http://bit.ly/P0xhDN)
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Hi sychro, can you do little diagram on how you'll have it wired? Im confused.
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If you look at the datasheet for that switch here: bit.ly/SrF12n (http://bit.ly/SrF12n)
On the second page is the schematic for the DPDT version.
+ -
Pins 2 and 5 to the display
pins 1 and 4 to the battery
pins 3 and 6 to the atty
With this switch configuration, position 1 would send atty volts to the display, position 2 would be off, position 3 would be battery voltage to the display. Pos and neg for both atty and battery can be switched in while being kept isolated from each other avoiding the problem reported with the DNA.
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Got it synchro! I was using a 3 way slide switch with 3 pins on my okr mod. I see that this one has 6 pins. Thanks man!
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Just moved the DNA to a different box, on the charge now. Charger is running at about 650mA with the resistor change so got a little bit more out of it. Charge rate is constant, not bouncing that I can tell.
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Put both the DNA's in a box this weekend with 2 1000mah lipos in parallel, that will blow your hair back. Really only useful for 1.5ohm dual coils as it still has the 6v limit. About 15w is my personal limit, above that it just tastes burnt to me.
Voltage display works as I thought, able to see battery and atty voltage no prob.
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Put both the DNA's in a box this weekend with 2 1000mah lipos in parallel, that will blow your hair back. Really only useful for 1.5ohm dual coils as it still has the 6v limit. About 15w is my personal limit, above that it just tastes burnt to me.
Voltage display works as I thought, able to see battery and atty voltage no prob.
Nice going synchro ;cheers;
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Hi, this is my first try of the dna. I was having troubles seeing the atty voltage a while ago then i realized it only show voltage underload. Ahahahahaha!!!! Will use the volt meter to show batt and atty voltage like sychro did. Just breadboarded everything.
(http://i1070.photobucket.com/albums/u491/poorboyvapes/9E012416-9D90-4C77-818B-2918D7EF391C-102-000000020D329DB0.jpg)
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Hi, this is my first try of the dna. I was having troubles seeing the atty voltage a while ago then i realized it only show voltage underload. Ahahahahaha!!!! Will use the volt meter to show batt and atty voltage like sychro did. Just breadboarded everything.
Nice start to a fine mod :popcorn:
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Nice, keep us posted! Love that pot you are using, they really add a finished look to the mod.
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Thanks! Just have a quick question, that pot has a 10kohms resistance which i got for around $10 and im not sure if my calculations are correct base on the voltage showing on the display. im getting like 13watts 6v using a 2.7ohms build on my RA. Not sure if the volt meter is accurate and when i dial to lower down the wattage i'm still getting 6v but a little less power. Is it because of the voltage limit of the dna or the pot that im using?
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Doesn't sound right, whats the voltage range from lowest to highest through the full range of the pot?
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3.8-6volts is the voltage range on a 2.7ohms atty. Maybee i need to use the evolv recommended wire gauges and see if there will be any difference. Right now im using 20gauge solid wires. Its just that when iam at max turn of the pot im getting 6v and when i'm lowering it down a bit still getting 6v.
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Sounds like you are hitting the 6 volt limit of the DNA with that atty. The pot sets wattage level, not voltage with the DNA so as it tries to achieve what wattage uou have it set to it runs into the voltage limit. 6 volts at 2.7 ohms results in about 13.3 watts - not too bsd a vape but definitely the max of the DNA.
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3.8-6volts is the voltage range on a 2.7ohms atty. Maybee i need to use the evolv recommended wire gauges and see if there will be any difference. Right now im using 20gauge solid wires. Its just that when iam at max turn of the pot im getting 6v and when i'm lowering it down a bit still getting 6v.
The minimum wattage setting is 5 watts. You should be able to lower the voltage when the pot setting is lowered. With a 2.7 ohm atty you should see approximately 3.67 volts to 5.69 volt range. Check your wiring particularly on the pot. Make sure the wiper (middle pot post) is on Pin 8 (W) of the DNA.
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I've put it all together, replaced the wires and its now functioning as it should be. Getting 5w lowest and 12.5max! Put it in an enclosure like zz has on his cloudmaker mod. Thanks breaktru, craig and sychro you've been an inspiration! Next target is with an mcu. Still learning some programming. :)
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Heres how it looks like
-set and forget
-ability to use as a passthru
-ability to show atty and battery voltage
-alluminum case for durability
-easy dial to your sweetspot (5w-12.5w)
(http://i1070.photobucket.com/albums/u491/poorboyvapes/100C1BEB-FC93-47F7-88C8-E973EBC0DE2D-220-00000030E3B78591.jpg)
Thanks breaktru, carighb and sychro for the inputs!
At some point im only getting 11.5 watts max on a 3ohms atty but that doesn't bother me i rarely use that resistance. :)
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Heres how it looks like
-set and forget
-ability to use as a passthru
-ability to show atty and battery voltage
-alluminum case for durability
-easy dial to your sweetspot (5w-12.5w)
Thanks breaktru, carighb and sychro for the inputs!
At some point im only getting 11.5 watts max on a 3ohms atty but that doesn't bother me i rarely use that resistance. :)
Very cool.. congrats poorboy.
I like the case. I know it comes in black and anodized silver and comes in two sizes. Yours looks grey, could be the lighting though. I have the same case for my Nokia MCU mod.
Nice quality pot. I've seen them before but a little expensive for me.
Did you use the AW battery from the breadboard?
If you like, you can start your own topic for your mod in the Modding category and I can move the related posts to it.
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Very nice work! Those have a nice finished look.
Where is that case from?
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Thanks! I name it KRATOS - god of strenght and power. Hehehehe. Your right breaktru that case is anodized black but it came with scratches so i paint it a bit with matt black. 2 of them uses aw and the other one is panasonic hybrid. Will probly use li-po next time.
@sychro the link for that case is in zz's thread in vf.
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For those of you that are looking for a parts layout, see attached drawing:
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Hi everybody.
I will made my second DNA mod and have a question.
Can I use only a Switch push for activate DNA ?
My first mod have a principal switch ON-OFF master but now i can use a mechanical switch push. I see like the Darwin and DNA have a small pulses for know if the atty is in.
Any problem with not use the principal switch OF - OFF for turn off the mod?
Thank very much and sorry for muy bad english.
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Hi everybody.
I will made my second DNA mod and have a question.
Can I use only a Switch push for activate DNA ?
My first mod have a principal switch ON-OFF master but now i can use a mechanical switch push. I see like the Darwin and DNA have a small pulses for know if the atty is in.
Any problem with not use the principal switch OF - OFF for turn off the mod?
Thank very much and sorry for muy bad english.
Not sure if having power to DNA without an ON/OFF switch will draw any power from the battery. I always use an on/off switch for max battery life and in case of an accidental firing of push button while in my pocket.
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Not sure if having power to DNA without an ON/OFF switch will draw any power from the battery. I always use an on/off switch for max battery life and in case of an accidental firing of push button while in my pocket.
Thank very much Haileah.
Darwin send small impulses all the time for calculate the impedance atty.
DNA have about 2,35V in Switch push atty. When you pust the swicth this voltage is cero and DNA is activate. I also discovered that DNA not send all watts when the atty is out.
My concern is that the DNA without switch master ON OFF is allways ON (mode lethargy but ON).
Thank very much.
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Thank very much Haileah.
Darwin send small impulses all the time for calculate the impedance atty.
DNA have about 2,35V in Switch push atty. When you pust the swicth this voltage is cero and DNA is activate. I also discovered that DNA not send all watts when the atty is out.
My concern is that the DNA without switch master ON OFF is allways ON (mode lethargy but ON).
Thank very much.
Yes the DNA won't fire without an Atty load but there may be a very small current drain with a battery connected all the time.
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Thank very much Haileah and Breaktru for yours answers.
I will try again put one sitch master On Off.
Here a picture of my first DNA mod. I use it for 3 weeks and am very happy.
(http://img.tapatalk.com/d/12/09/10/8ymy7yty.jpg)
Best regards.
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Thank very much Haileah and Breaktru for yours answers.
I will try again put one sitch master On Off.
Here a picture of my first DNA mod. I use it for 3 weeks and am very happy.
Best regards.
:beer-toast:
Excellent looking mod. Well done vaporvolt.
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Yes, looks really nice. Looks like you have a nice selection of atomizers too.
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;)
Thank very much.
None of this would have been possible without his advice. :yes"
Thanks to all who share their work.
;bow;
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Cool man! Congrats! Looks like we have same pot and button. :)
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Wow, lots of great info and awesome looking mods guys!
I'm considering building my first mod and decided to focus on the dna for it. In the process of gathering parts right now and had a couple questions.
I want to put in an led volts display for atty and battery voltage. Any recommendations on good working displays?
Also, where would be the best place to put a firing indicator led in the circuit?
Can it be put on the fire button, or should it be on the atty side?
Thanks!
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Problem with driving the LED with the atomizer output is that it will vary in brightness depending on voltage selection. Assuming the trigger is on input power (typically the case), it would be better to drive it with input voltage from the battery. It will still vary a bit, but not as much. If you want to, you could drive the LED with a little LDO regulator.
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Thanks for the reply :)
I see on the datasheet for the dna the switch (pins 1 & 2) is for logic function for internal power switching. Does this mean there is no voltage on these pins? I can't ind any info on it.
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Good day kott. My volt display is a attached to 10and11 for the atty voltage and 5and6 for the battery voltage using a DPDT switch. If you you want to know how you'll connect it just read synchros earlier post here. :)
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Good day kott. My volt display is a attached to 10and11 for the atty voltage and 5and6 for the battery voltage using a DPDT switch. If you you want to know how you'll connect it just read synchros earlier post here. :)
Thanks Poorboy, could you tell me where i could get an led display similar to what you are using?
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I only got that from a friend i think its from china. I saw it on ebay. :)
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I only got that from a friend i think its from china. I saw it on ebay. :)
you might try http://www.adafruit.com/products/460
http://www.adafruit.com/images/minivotmeterquarter.jpg
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Vaporvolt, great looking mod.
Question for the group. How could I go about having an lcd readout like Breaktru's? I know it has to do with programming a chip but I don't know for sure. Where is a good place to learn about this? I think you have to have a board that you program it through.
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Vaporvolt, great looking mod.
Question for the group. How could I go about having an lcd readout like Breaktru's? I know it has to do with programming a chip but I don't know for sure. Where is a good place to learn about this? I think you have to have a board that you program it through.
This is a start http://mcu-programming.blogspot.com/
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I didn't even know that they were called that. Thanks.
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There is also a lot on this site http://en.wikipedia.org/wiki/Microcontroller (http://en.wikipedia.org/wiki/Microcontroller)
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You can do a voltage meter and a VV output without anything other than a simple schematic and a few off-the-shelf parts. However, when you want to start adding things like resistance and power indications, you're jumping up to a whole new level of electronics. That's the stuff you have to engineer yourself. There's nothing off-the-shelf for that. Though I can see Evolv offerring something that does eventually. They seem to be heading there.
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For those of you that are looking for a parts layout, see attached drawing:
just what I needed :) thanks man...
and nice to see a fellow filipino vaper here... hello, boss poorboy! :)
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just what I needed :) thanks man...
and nice to see a fellow filipino vaper here... hello, boss poorboy! :)
Hi Ginjo! Looks like your building your own dna mod. You can hit me up here or at pvf anytime man!!! :)
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Hi Ginjo! Looks like your building your own dna mod. You can hit me up here or at pvf anytime man!!! :)
I think I just did yesterday boss :D
still sourcing and checking if its doable at my skill level :)
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Im sure you can do it ginjo. What battery are you using? Are you going to use its charger?
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planning to use the charger, with 2 imr 18650 2K Mah batteries
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Haven't tried that yet ginjo. Maybe this will help http://breaktru.com/smf/index.php/topic,543.msg5092/topicseen.html#msg5092. Let us see your mod once it is done. :)
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well, I won't be doing it until next year, due to budget constraints :)
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well, I won't be doing it until next year, due to budget constraints :)
Sorry to hear it Ginjo. Well next year is only 2 1/2 months away.
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Sorry to hear it Ginjo. Well next year is only 2 1/2 months away.
i'm not sorry, coz i'm sure it will be worth the wait, and besides, I have to really make a plan of action and try to be as concise and careful as I can be for this... coz this will be my modding jewel if this pushes through lol
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Thank very much Haileah and Breaktru for yours answers.
I will try again put one sitch master On Off.
Here a picture of my first DNA mod. I use it for 3 weeks and am very happy.
(http://img.tapatalk.com/d/12/09/10/8ymy7yty.jpg)
Best regards.
Where did you get the box for the mod and what does it look like on the inside? Great job by the way.
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Where did you get the box for the mod and what does it look like on the inside? Great job by the way.
The box is a charger pc box. Inside battery LiPo, but i put two AW IMR 18350 in paralel.
Thank you.
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Down sized box for the MCU DNA12. See attached photos (logged in members only)
Still works great
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Down sized box for the MCU DNA12. See attached photos (logged in members only)
Still works great
Much nicer enclosure IMHO.
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Looking good. Gotta love a smaller enclosure.
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Better for sure :applaude:
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Looks fantastic! This thread has been a great help for me planning and designing my first DNA12 mod... trying to make it as small as possible :)
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Looks fantastic! This thread has been a great help for me planning and designing my first DNA12 mod... trying to make it as small as possible :)
Welcome to the forum thadass. What box will you be using for your DNA12 mod?
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Looks fantastic! This thread has been a great help for me planning and designing my first DNA12 mod... trying to make it as small as possible :)
+1
Oh Yeah!
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Welcome to the forum thadass. What box will you be using for your DNA12 mod?
An Altoids Smalls mint tin, which have a usable space of about ~50mm tall, ~35mm wide, and ~15.5mm thick. Volume wise it's about 30% smaller than the 9v madvapes box. No real reason other than enjoying the challenge of an unusual container, and I think it'd make a very portable stealthy VW experience. I have several test models set up in SketchUp but some of the margins for clearance are admittedly aggressive and improbable. As soon as I have selected some lipo batteries to test and have the dna 12 board as well and think I have something reasonable to work on, I'll probably start a thread for it :)
... the "in a perfect world" models.
(http://imageshack.us/a/img196/2853/26711842.png)
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An Altoids Smalls mint tin, which have a usable space of about ~50mm tall, ~35mm wide, and ~15.5mm thick. Volume wise it's about 30% smaller than the 9v madvapes box. No real reason other than enjoying the challenge of an unusual container, and I think it'd make a very portable stealthy VW experience. I have several test models set up in SketchUp but some of the margins for clearance are admittedly aggressive and improbable. As soon as I have selected some lipo batteries to test and have the dna 12 board as well and think I have something reasonable to work on, I'll probably start a thread for it :)
... the "in a perfect world" models.
:thumbsup: Looking forward to the new mod thread of yours
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I like the idea of getting them smaller and smaller. The DNA12 is perfect for tiny mods I think. I haven't tried a mod with a lipo yet. I have a couple lip's sitting here waiting though.
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I haven't tried a mod with a lipo yet. I have a couple lip's sitting here waiting though.
Lipo's are great. Once you go LiPo, you'll never switch backo :laughing2:
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They are nice, they have much lower internal resistance than a round cell. They fit nice in a box and the tabs are easy to solder. The one down side is they don't have the highest energy density, it's actually somwhat lower than an IMR 18650. So, you'd actually get better run time for the size with an 18650 tube. Though the energy density is about the same compared to an IMR 18350 since for the round cells, energy density gets lower as the cell gets smaller. The flat cells seem to maintain their energy density as they get smaller.