ok will try. I mean I can change them after i get them at the end of feburary.
Nevertheless i will continue soldering 
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Thanks, this one got through review and is now in production. So either the dummy traces you added helped or it is random based on the person doing a manuel review.
No more green leds, so I took yellow instead.
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I looks perfect man… 
What about large capacitors? I don’t know if you’re using those from the BOM, but I just found an error yesterday in the LCSC order number. It should be C443085, and the BOM and documentation is updated. However, if you don’t plan to go to 75V, you can find some that are cheaper with 63V spec. You should go for D=10mm (diameter), then you can mount 6 of them - it will fit the spacing on the board.
I think it is more or less random. If you don’t order a lot at jlcpcb, maybe they go more in detail with the review, because you’re more likely to make an error if you’re a novice. I think you just wait for the next shift to start working, and it will pass through.
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Six capacitors of diameter 10mm will fit the board. Don’t let the capacitors pass through the holes in the board. Just solder them to the surface.
(here I actually used 63V 330uF. Those in the BOM are spec’ed for 80V (5 mm longer)
Bending the caps at the right spot is an advantage, if you want to use the screw holes at some point.
Even when the power module is attached, you can get to the screws with a small screwdriver. But the accessibility of these holes is something I need to fix in another version.
Just a side note guys…those ceramic caps are being drowned in solder and that can crack the caps. They hate that much heat.
Same for any components…minimize the soldering time and don’t trap them in piles of solder that will expand/contract when thermally cycled. That’s another way those ceramic caps can get cracked.
Don’t try to lower pcb trace resistance with solder. Redesign the board (larger planes, heavier copper, etc) or use “bus bars” (solid wire, whatever).
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Don’t use that much solder!!
So far my impression has been that exposing copper planes and applying a layer of solder is not really to conduct current, but more to conduct heat. Fast removal of heat from mosfets. Solder is a bad conductor of current, but a good conductor of heat.
Is this view on exposed copper planes the correct view?
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Fast removal to where?
If you can’t get the heat out of all that solder then it will “heat soak” and quickly rise in temp, doing little to cool the FETs.
If the FETs need this kind of, IMO, desperate measures for cooling then the system needs a redesign. 
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Not talking about the amount of solder on the image about - talking about exposed planes with solder in general. Conduct current or conduct heat?
above
There is the possibility that I have misunderstood why the solder mask is removed on the planes that conduct a lot of current. Why is the copper exposed to free air that will corrode it? Is the purpose to allow faster transfer of heat from copper to air? Should you apply solder to these areas?
What’da purpose?
That’s a nice DRV chip you’ve got there. 
I asked ChatGPT, and off course you should take it’s answer with a grain of salt sometimes:
You
In pcb design of power electronics you sometimes see that the solder mask is removed on large copper planes that conduct a lot of current to the legs of switching mosfets. By removing the solder mask you expose the copper to free air that will corrode it over time. Why do you sometimes remove the solder mask (laquer) in such pcb designs?
ChatGPT
ChatGPT
Removing the solder mask (lacquer) on large copper planes in power electronics PCB designs is often done for thermal management reasons rather than for enhancing electrical conductivity. This practice is particularly common in power electronics circuits, where components such as switching MOSFETs generate significant heat during operation.
By exposing the copper directly to the air, you improve the thermal conductivity of the copper plane. This allows better heat dissipation from the MOSFETs or other high-power components to the surrounding environment. The free air surrounding the exposed copper acts as a natural heat sink, helping to dissipate the heat generated by the components more effectively.
Improved thermal management is crucial in power electronics to prevent the components from overheating, as excessive temperatures can negatively impact the performance and reliability of the circuit. The removal of the solder mask enhances the ability of the copper plane to transfer heat away from the components and, consequently, increases the overall thermal efficiency of the PCB.
While exposing the copper to air does make it susceptible to corrosion over time, the benefits of improved thermal performance often outweigh the potential drawbacks. Engineers may choose specific surface finishes or coatings to mitigate the risk of corrosion, depending on the specific requirements and environmental conditions of the application.
You
Should you apply a layer of solder to these planes?
ChatGPT
ChatGPT
Applying a layer of solder to exposed copper planes on a PCB can provide additional benefits in certain situations. The decision to add a layer of solder typically depends on specific design considerations and the intended function of the PCB. Here are some factors to consider:
- Improved Thermal Performance: Solder has better thermal conductivity than the bare copper, so adding a thin layer of solder can enhance the thermal performance further. This can help in better heat dissipation from the components.
- Corrosion Protection: Solder acts as a protective layer, helping to prevent the exposed copper from corrosion. It forms a barrier that shields the copper from the surrounding environment, which is important when the PCB is exposed to conditions that could lead to corrosion.
- Solderability: If you plan to solder components directly onto these exposed copper planes, applying a thin layer of solder can improve the solderability of the surface. This can simplify the assembly process and ensure good solder joints.
- Electromagnetic Interference (EMI) Considerations: In some cases, applying a layer of solder can help reduce electromagnetic interference by providing additional shielding.
My post refers to that too.
It is done in some designs to help lower the plane’s resistance .
It is done in some designs to help conduct heat away from a component.
This does not mean it is effective at either of these things.
This is only true, a bit, where convection can occur. If there is no air flow or if there is no room for convective air currents to form then there will be almost no benefit to removing the solder mask.
Metals are really bad at radiating IR energy (heat) away in order to cool themselves, that is, their emissivity is low. By having solder mask on the bare copper you significantly increase the ability of the copper to get rid of heat, you raise its emissivity.
Since radiative cooling can occur even within a small closed space then you could get more cooling by using a solder mask versus bare copper (or solder over copper).
The details matter here though and every pcb and operating environment can change which method might be better.
Using solder on the copper can help with those four things but only to certain degrees. Again, the details matter.
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A thin layer of solder won’t help with radiative or convective cooling. A thick layer of solder can help lower the thermal resistance of the copper plane to a component but what will you do with the heat you pull away? The effectiveness of the added solder is limited if you just have a blob sitting there. And the huge amount of heat you dump into the component (to get the solder in place) really goes against what you’re trying to achieve…a more reliable system.
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I agree. It can reduce corrosion if in a high-sulfur (airborne) environment. Standard HASL finishing of the pcb can do this, no thick layer needed.
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I agree. Using a thin layer of solder (HASL coating) is an also great thing to do in order to keep the pcb solderable over time.
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While technically correct for some setups the rest of the circuit also needs to be equally hardened against EMI. The signal strength needed to blast through just a standard 2oz copper plane ground plane is crazy high. Adding solder to just some spots, leaving all the others unprotected, in such a high EMI environment will quickly result in product failure.
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Yo pps , I’m new here , eu based , anyone want to do a group buy for the f of c ? I don’t need 5 of them , I only need 2 , and to order 2 vs 5 is only 60 euro less . Or does anyone want to sell 2 for a “normal” price. Worst case I will order 5 as I don’t see much of a point of ordering 2 but then the project will have to wait a month so I can financially support it
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When you assemble pcbs you receive from jlcpcb. I advice you to do ALL the tests specified in the Assembly Guide. This will highly reduce the risk of creating shorts or other errors.
If you order I would be happy if you write a short note in this thread - and tell about how everything went, etc.
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