Using a 12V DC power supply

[TheBloke]

OK thanks a lot guys.  I do intend to analyse, but likely not to the extent or sophistication that you will be SSV!

Once I've got settled in I will wire up the battery and do some comparisons, see if I can detect any difference.  

That LifePo4 does look good, something I might consider in the future.

[SSV]

TheBloke said:

OK thanks a lot guys.  I do intend to analyse, but likely not to the extent or sophistication that you will be SSV!

Once I've got settled in I will wire up the battery and do some comparisons, see if I can detect any difference.  

That LifePo4 does look good, something I might consider in the future.

Typically removing the uncertainty in a DUT is only relevant when something goes wrong and you have to troubleshoot...the big 12v cell array is a very cost effective option for clean and predictable power....it's $100 vs a couple grand for a nice 30A linear tdk/lambda reference supply...the reference supplies still need to be characterized and nulled from the DUT. When dealing with vREF applied to a/d converters even running through multiple in line linear DC regulators won't solve a hard oscillation or other problem from a switching source...the linear Reg can smooth some noise but if the supply is oscillating sometimes the in line linear regulators won't have enough pre-bias to stabilize their junction and they can swing in junction resistance....thus can show up as a deviation down the line in the vREF driving the a/d

[alee132]

mikepetro said:

23A on the input is all that is required.



That power supply would be overkill for whats needed.

The 55A is the OUTPUT max, not the INPUT.

Ok cool I hadn't actually looked at the spec sheet yet, I had heard 55amp somewhere. But now I wonder why if they only need 23amp input why in the heck they even need such high output lipo's?  Oh maybe its because they wanted to have the input voltage be higher than the output voltage so it could be a buck only chip, instead of buck/boost.  Because I would think that 2 18650's in series would be way more than enough amp's or a 2s lipo in series. Actually this makes me happy personally because I can now get a lot cheaper of a power supply.  Thanks for setting me straight!

[VapingBad]

23 A x 11.1 V = 255 W
255 W / (3.7 V x 2) = 34.5 A
There are no 35 A continuous 18650 that I know of, plus the risk of users reversing them, the size and the need to keep them in pairs for life.

[John]

The issue is really more at low battery than at nominal voltage, so the math goes

23A * 9.1 = 214W

214W/(3.0*2) = 35.7A

And I agree 100% there are few realistic continuous 35A 18650 cells. There are ones that can do it as a parlour trick, but not all day every day. 

[VapingBad]

I know that's the pressure point, just trying to keep it simple with the nominal values.

[John]

The new update that just went up should fix the blinking in power supply mode. Let me know if you run into any problems with it. 

[HPBotha]

looking into making a 'home' mod as well... would the following power supply work fine:

http://www.jun-si.com/EnProductShow.asp?ID=95

Input Voltage Range	100?240VAC	Output Voltage Range	14.9?15.5VDC
Input Frequency	50/60Hz	Output Current	0?23A
Power	350W	Efficiency	88%

[Spector NS5 RD]

HPBotha said:

looking into making a 'home' mod as well... would the following power supply work fine:

http://www.jun-si.com/EnProductShow.asp?ID=95

Input Voltage Range	100?240VAC	Output Voltage Range	14.9?15.5VDC
Input Frequency	50/60Hz	Output Current	0?23A
Power	350W	Efficiency	88%

my original post was incorrect. the absolute max voltage for the dna 200 is 16 volts. so yes, that power supply will work.

[koma2k]

Just to be on a safe side:

A car battery should work just fine then, right?

I'm in a process of designing a "party vape-station": basically a car battery in a nice wooden box, on the box 4 (or more) high-amp outlets and and end mods like in stationary vape stations made with AC/DC power supplies, equipped with dna200's.

[VapingBad]

koma2k said:

Just to be on a safe side:

A car battery should work just fine then, right?

I'm in a process of designing a "party vape-station": basically a car battery in a nice wooden box, on the box 4 (or more) high-amp outlets and and end mods like in stationary vape stations made with AC/DC power supplies, equipped with dna200's.

Do the math for the particular battery (9-12.6 V & 23 A), but as far as I know most car batteries will hold voltages above 12.6 V so you probably need voltage regulators at least.

[blueridgedog]

I would search the forum, but another person had the idea to do this and I "think" a staff member from evolv said the typical high end from a standard vehicle 12 volt would work.  Double check.