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Good cheap way to get rock solid 12V DC output?
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mariush:
Like everyone says, the guy probably means the motherboard doesn't have built in protections against reverse voltage or over-voltage events or "dirty power" which could happen in automobiles.
So, you're not supposed to power the board from the cigarette lighter for example, if you still have one.

It will work just fine from its own separate power supply, or let's say from a 18v laptop adapter powered from an inverter connected to your car - the inverter has the protections and converts power to AC and then the laptop adapter converts back to DC along with filtering and smoothing and everything.... would not be the most efficient process but it would be safe.

The board will run just fine from a lead-acid battery, which will have voltage between 10v and around 13.8v when fully charged. 

The VRM on the motherboard will probably be more efficient if your voltages are closer to the upper end, as the input current is lower this way... but it really depends on the implementation.

If you want more lightweight, less space... then i would aim for a 4S (4 in series, or multiple sets of 4 in parallell) lithium battery, along with a proper charger, like this one for example: https://hobbyking.com/en_us/imax-b6-50w-5a-charger-discharger-1-6-cells-genuine.html?___store=en_us
Same website has batteries compatible with the charger, for example this one: https://hobbyking.com/en_us/zippy-compact-3700mah-4s-25c-lipo-pack.html  or https://hobbyking.com/en_us/zippy-compact-2700mah-4s-40c-lipo-pack.html (higher discharge current if your board uses lots of power)
(they have bigger capacities but this has good price per mAh)


 
Zero999:

--- Quote from: SpannersToSparks on November 26, 2018, 11:11:33 pm ---Because it is highly sensitive to fluctuation, even though it has a wide operating range. It has a lot of expensive sensitive components I guess.

You are not alone in asking that question, but the manufacturer assures me stability is paramount, even if they seem to be singularly unwilling to advise me how to achieve that (liability I guess)  : (

--- End quote ---
It won't be sensitive to fluctuation, because of its wide operating range.

Has the manufacturer actually given a definite specification for the power supply, other than 5 to 19.5V?

It will have its own voltage regulator built-in.

The only thing you need to run it off a large battery is a fuse, fitted in a suitable holder, as close to the battery as possible. If you don't know what fuse to use, look at the output current rating of the wall-plug power supply and use a slightly higher current fuse than that.
KL27x:
Perhaps they will be more willing define what is not rock steady slightly better after each time he files for a warranty repair/replacement.
perieanuo:
Hi,
Well without defining 'rock solid' this discussion is going nowhere.
Didn't mean to be a asshole but technical correct answer needs knowing the specs.
Regards,pierre


Envoyé de mon iPad en utilisant Tapatalk
spec:
Hi SpannersToSparks,

You are not to specific about the current demand of your equipment, so I will read between the lines and assume that the supply requirements are any voltage from 5V to 19.5V DC, and a current demand of 0A to 3A.

The module that you describe is a switching power supply which would introduce noise and anyway seems unnecessary.

If you go for a fairly benign discharge regime for your three LiPo batteries the minimum discharge voltage could be 3V each, giving a total of 9V minimum. The maximum voltage for three fully charged LiPo batteries would be 12.6V.

With this raw supply voltage range you could use a linear regulator to provide a fixed 5V.

If this approach appeals just say, and we can discuss the measures necessary to make a standard regulator circuit really solid.  :)
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