LDNIO DL-AC318 Triple usb 2.1A


Official specifications: I got this charger from Banggood SKU: 187914

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I got this charger in a retail package.

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Here the model number is DL-AC318


The X on top of the charger has a blue light behind it.

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The charger has 3 outputs, one marked Galaxy tab and two marked iPad



First test is the Galaxy connector, it can deliver about 2.2A before is shuts down (Very nice).


The other outputs are the same, because they are in parallel.


This adapter has a US plug, i.e. it is mainly for 120VAC, the lower voltage does not really affect output, but it do reduce efficiency slightly.


There is no problem delivering 2.1A for one hour.

The temperature photos below are taken between 30 minutes and 60 minutes into the one hour test.


M1: 45,8C, M2: 48,7C, M3: 58,0C, HS1: 65,2C
It looks like HS1 is D5, but I wonder why it gets hot.


M1: 44,9C, M2: 38,1C, HS1: 68,6C
Again it looks like D5.


M1: 61,5C, M2: 45,0C, M3: 37,3C, HS1: 65,4C
HS1 must be the mains switcher transistor and M1 must be the transformer


M1: 48,8C, M2: 44,2C, HS1: 50,8C


M1: 56,1C, M2: 57,4C, M3: 53,8C, M4: 42,3C, HS1: 66,5C


With 0.5A load the noise is 25mV rms and 250mVpp


With 1A load the noise is 36mV rms and 260mVpp


With 2A load the noise is 47mV rms and 310mVpp

Tear down


The first you check when opening a device without visible screws is for hidden screws behind rubber feet and labels. I have been opening many usb chargers recently, they have all been glued and forgot this. After some work with my vice and a screw driver as crowbar I could see inside the charger and see the screw. Then I could open it without doing any more damage.
Sorry about the scratched circuit board.

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On the mains input side there is a fuse, a inductor and a mains switcher transistor. There is also the safety capacitor.
On the output side there is the rectifier diode.


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The fuse is easy to see here, it is a glass fuse without any cover.


Here the blue led can be seen (It is clear, only the light is blue) and behind the led is the rectifier diode.


On this side of circuit board the input rectifier bridge and the mains switcher controller can be seen.
Also note the model number, here it is DL-218 where the outside of the charger says DL-AC318.



The distance between mains and low volt side is slightly below 4 mm, this may be fine for 120VAC, but the charger is marked for 240VAC and there it is not enough.

Testing with 2500 volt and 5000 volt between mains and low volt side, did not show any safety problems.


Generally it looks acceptable, noise is fairly low and it can maintain output with full load, but I would have like a Android usb output (DCP).
The safety is fine for 120VAC usage, but not legal in 230VAC country.


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