Pads 9.5 manufacturing problem inquiry

bluemingchu

Pads 9.5 manufacturing problem inquiry [Copy link]

I want to make a component with a grounding copper foil under the CPU, but I don't want to remove the solder mask all over, and there is green paint solder mask on some parts. Is there a way to design it like this?

qwqwqw2088

Does it mean there is a grounding copper foil under the CPU?

qwqwqw2088

The size of the ground pad is shown on the back of the CPU data sheet

Make a component package according to the pad size diagram

How to ground the pad? The copper needs to be exposed, so a window needs to be opened in the solder mask layer, which means that the area that needs to be exposed copper will not be covered by the solder mask green oil. The solder
mask opening area is a certain size larger than the actual pad, and it is recommended to be 4mil or 0.1mm

bluemingchu

I can make the parts by pads, and the copper foil under the CPU is as shown in the photo. However, I don't know how to use it to add some green paint to the large piece of copper foil.

qwqwqw2088

Green paint is the green oil layer, that is, the solder mask layer

Large piece of copper foil, that is, bare copper on the pad, or exposed copper foil on the pad

The pad will open a window by default in the design, without the trouble you imagine

Large areas of exposed copper are designed according to the pad, and the same window design is also used.

qwqwqw2088

It is very simple to open a window in pads. Just draw the shape of the window you want on the solder mask layer. If it is a top window, then draw it on the solder mask top.
The same is true for pads 9.5

bluemingchu

I want to process the parts in the manufacturing process. What does the square pad in the middle of the specification book mean?

bluemingchu

If I just want to shrink a certain pad solder mark, not the pad solder mark of the entire component, is there any way to do it?