Review: NANJG 105A 2800mA driver

Today I received my driver. It`s 105C from DX ! I don`t know why but it works on half power ... High 1,4A , Mid 0,4A , Low 0,08A

I did solder all like on this photo. Any ideas why i can get the full power ?

Why did you solder the pins of the MCU like that and why haven't you used the stars to get your desired group of modes?

I didn`t touch the MCU ! I forgot to say ...

I see. You measured half on everything, Hi, Mid, Lo.

Maybe you can post some photos of that particular driver.

Yes ! Exactly the half on everything, Hi, Mid, Lo ! Don`t have photos of my driver yet but it looks exactly the same like this on the photo ...

I think that the 7135 devices from one on the sides of the PCB doesn`t work at all ....

Regulation test someone? Will be very grateful :)

earlier I made one, but with a 3040mA version

https://budgetlightforum.com/t/-/6690#node-7789

It is most likely a bad connection between the two sides of the print. All 7135 should be connected in parallel. Try with an ohmmeter or a continuity tester between corresponding legs of one 7135 on the upper side and one on the lower side and repair the missing connection (if any).

So, no regulation? I've tried to measure ohm of my Trustfire with my UNI-T and got 0.

Thank you for the advise my friend ! Will test and report here !

It is regulated, but buck only. You cant measure the internal resistance of a battery with a multimeter just like that, you may have killed the fuse..

I did check and all connections look fine !

Same as you
I get half of the power, and tried on 2 of these drivers.
I checked out the AMC7135 one by one and they all work.

At the end I still get 1.4A on high…

I tried to replace the wires with thicker wires, but no change

The input and output to/from the chips on each side are connected by the tiny holes(vias) in the board. If through a manufacturing error, those holes did not get plated, you will only see the output from one side. Measuring the resistance between corresponding legs on opposite sides will verify this. It should be zero for both Vdd and led-. If that is the problem, jumpers to make the two connections will fix it or you could send them back for replacement.
Edit- there appear to be 3 vias in question. Ignore those connected to the stars. In the first image at ~ 10 o’clock are 2 vias in line with the red arrow. The one toward the center of the board is Vdd and the mcu uses this trace to turn the chips on and off(pwm signal). The one toward the edge is the output where the current from the led is dispersed to the chips and through them to gnd. At ~ 1 o’clock is another via that connects other chips to the output trace. If you look carefully at the images you can see how the vias are used to complete the parallel connections of the chips. Some of the traces pass under the chips to do this.

I tried with another driver, I am stuck at 1.6A

Also how big are your wires connecting the led to the driver ?

I have wires made of 5 thin wires, and 7 thin wires. I currently only use the one made with 5 as it is more flexible and easy to solder on the board. But I am wondering if this is big enough

I am really wondering how you guys succeed in getting 2.8 or 3A, because I have now 3 drivers that should give 2.8A each, and I can’t barely get 2A…

All of the 105c’s I have tested in my lights do put out 2.8 amps on high.

My first thought is: What kind of battery are you using? Is it capable of 2.8 amps? Some are not.

It could also be your DMM...

Just wired one up worked for a few seconds now its stuck on High? Any ideas?

Check the negative on the led, its probably shorted to the ground

Thanks il give it ago!