N30820 driver pcb

N30820 laser module
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shades66
Posts: 4
Joined: Mon Sep 20, 2021 11:40 am

N30820 driver pcb

Post by shades66 »

Hi,

I have 2 N30820 lasers, 1st one came with the "NEJE Master 2S 20W" that appears to of burnt out in just under a month (mostly used at around 40-60% power so hoping just a one off dud diode) and a 2nd one which was supplied by the shop I bought from (not NEJE direct unfortunately) to replace the first one which also appears to be dead on arrival.

What I'm wondering is if the controller on the 1st one can be used to replace the controller on the 2nd one as the laser diode itself appears to be fine it's just the controller itself that seems to be broken? My reason for asking is that the boards on the 2 lasers appear to be totally different (1st one has two SSOP8 looking chips driving a fet/inductor circuit whereas the replacement one has a single SSOP8 & what looks like a SOT23-6 chip driving a similar arrangement) so I'm not sure if they are driving different voltage/current ranges).

Cheers
Mark
dav
Site Admin
Posts: 113
Joined: Sat Nov 21, 2020 4:00 am

Re: N30820 driver pcb

Post by dav »

Hello, the driver is the same. The new driver at the back has optimized surge protection. The current is 3.2A. NEJE optimizes the driver efficiency very well, and the internal heat dissipation design. If you are damaged during use, you can get free after-sales service. Yes, NEJE modules provide 2 years of free after-sales. You can go to the store where you purchased to get new modules, if it is because of product quality problems;
shades66
Posts: 4
Joined: Mon Sep 20, 2021 11:40 am

Re: N30820 driver pcb

Post by shades66 »

Hi Dav,

Thanks for the reply. I am working with the shop that supplied the machine and they are now sending out a second laser module so fingers crossed that works :) They have also said I should dispose of the 2 faulty lasers instead of sending them back.. and as I like to see how things work I thought I would have a good look and see what's inside :)

How do I identify which is the newer driver? The text on the 2 dead modules have the following text on the PCB's

1) NEJE A3.2 - This was on the replacement module which was dead on arrival but I believe the Diode itself is working
2) NEJE A3.2 v3.0 - This was on the original laser module I received with the Master 2S which the Diode has died.

I'm thinking the one with v3.0 is new the better design?

Investigating further on the replacement driver I assumed that the STC processor was the problem as it felt warm but further investigation shows that it's one of the 2 tiny SOT-23 components directly behind the STC chip which get very hot as soon as the board is powered up (from the caps & transistors around them I'm guessing a transistor for the fan and a regulator for the STC chip?)

Thanks
Mark
dav
Site Admin
Posts: 113
Joined: Sat Nov 21, 2020 4:00 am

Re: N30820 driver pcb

Post by dav »

Hello, it is normal for the chip to generate heat. The NEJE laser driver has been tested in the laboratory for a long time, and the chip temperature is within the range; the latest version of the NEJE module driver has better safety protection, and it has a surge. Safety design such as protection; NEJE modules are delivered to users through the strict production process and protection of the NEJE factory. If your modules are within the safety warranty period, NEJE provides free after-sales services, please rest assured to use; During the process, follow the instructions of the factory to take care of maintenance measures to ensure that the heat dissipation of the module and the lens are kept clean, and pay attention to safe use;
shades66
Posts: 4
Joined: Mon Sep 20, 2021 11:40 am

Re: N30820 driver pcb

Post by shades66 »

Hi Dav,

So I got my 2nd replacement laser from the seller and now have a working machine again !!

As for the 2 dead ones I swapped over the driver boards and now have a working module so I'll keep that as a spare in case the new replacement needs replacing again (hopefully the original laser was just a one-off dud that died after approx 40 hours). Obviously I won't expect that to be sorted under warranty now that I have taken it apart and swapped the drivers myself.

For the faulty driver I found that the component that was getting hot, and I mean within seconds of plugging the module into the tester board it was far too hot to touch, was the SOT23 regulator that I assume is some variation of a LM05 regulator that was reading as a short over the 12v & GND rails. I replaced that with a known good component and that board too now appears to be fine.

End of the day the seller of the machine has now sorted me out and I can start cutting/engraving again.

Thanks
Mark
dav
Site Admin
Posts: 113
Joined: Sat Nov 21, 2020 4:00 am

Re: N30820 driver pcb

Post by dav »

I’m glad to help you solve the problem. NEJE’s built-in driver is designed to be within safe temperature. NEJE engineers redesigned the driver for testing under the condition that it passed the test for a long time without fan cooling, but the actual situation is that the built-in driver uses the fan to dissipate heat. It can more effectively ensure the heat dissipation of the driver, and you can use it with confidence; if you have other questions, you can contact me.
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