The traditionally green coating which protects copper on PCBs from oxidation and shorting due to solder. Use this tag for PCB design questions and soldering questions which require attention to the mask layer.

learn more… | top users | synonyms

0
votes
1answer
46 views

Solder mask custom shape in altium

I want to have a region in my PCB without solder mask while the other regions should have solder mask. I am not sure how do I do it in Altium? To be precise I want say a custom shape solder mask free ...
1
vote
0answers
58 views

Solder mask free regions on PCB

I have noticed many PCBs with solder mask free regions/areas on the edges. I am attaching an image with this. What is the purpose of such areas ? What I can think of is heat transfer to the ambient ...
2
votes
2answers
274 views

Eagle - non solder mask defined (NSMD) pads

I am designing a PCB layout in Eagle and in the datasheet of my modul it is said that "Non solder mask defined (NSMD) type is recommended for the solder pads on the PCB". Does it mean that there will ...
1
vote
1answer
81 views

Coating a soldered connection on a small circuit board

I have a small PCB, about the size of a quarter and having a Bluetooth chip on it. I have 4 wires soldered to the board. 2 of which are for a 3.7 Volt battery connection and 2 are to connect a small ...
1
vote
0answers
93 views

How to remove silk screen from PCB?

Last batch of PBCs I got from a manufacturer had some silk screen splashes (dots) all over the board ruining the design. I don't have and don't want to have any silk screen on the board. The whole ...
3
votes
1answer
226 views

Should there be solder mask under this QFN-16 chip?

The layout for a QFN-16 packaged chip (FXOS8700CQ) I am using is shown below. I'm confused about the solder mask opening. Should it be everywhere inside the green outline or just rectangles around ...
1
vote
2answers
99 views

Soldermask impact to guard-ring circuit

Guard-ring circuit is designed aroung high sensitive (low current high impedance inputs). What is the technical impact if a guard-ring circutry is fully masked versus unmask ?
9
votes
2answers
708 views

Strange Solder Spots on PCB

I was tearing down some old CD drives and while taking a look to the PCB I found two pointy solder spots, connected to the first pin of each side of a chip which makes me think is an EEPROM. There ...
0
votes
1answer
144 views

Solder Masking Ink

I am trying to make a complete PCB with solder masking and silk screening, for creating a small PCB fabrication house of my own later. I choose the process of screen printing for fabricating my pcb, ...
1
vote
1answer
129 views

Solder mask for 0.5mm pitch TQFP

I'm using Atmel SAM chips and the data sheets don't have any mention of solder mask clearance for their TQFP packages. What would be a nominal pad/solder mask opening/cream size for a 0.5mm pitch ...
4
votes
2answers
537 views

Gerber - is my understanding of solder mask layer (GTS / GBS) correct?

I've just had a PCB manufactured for me, but it seems like the solder mask is only applied to where the copper is. I'm trying to figure out if it's my fault or not. According to my understanding ...
2
votes
0answers
171 views

Solder stop mask and tinning sequence

Is it recommended to tin PCBs before applying solder stop mask or should I apply the solder stop mask to the PCB and then apply the tinning? Would tinning before applying the solder stop mask be ...
9
votes
5answers
3k views

How to remove solder mask?

I'd like to reuse a PCB in non-intended way and I have to remove the green solder mask to expose the copper traces in 1 x 3 cm area. Is there any safe method to do it without damaging the traces? ...
12
votes
1answer
10k views

Solder Mask and Cream in Eagle

I've got this part specification for the Paste Mask excerpted from the datasheet: There's a lot of lingo in this short paragraph that I would like to better understand conceptually. Specifically I ...
11
votes
1answer
863 views

Solder Mask Color Code

Is there standard that recommend guidance of particular colors of solder mask? A while back I was told by a local assembler that BLUE typically indicates the circuit is ROHS compliant. Yet my Google ...
4
votes
1answer
627 views

Why are the pads different for THT / SMT components in Eagle?

I am learning Cadsoft Eagle and have noticed that the pads for SMT devices are on the 'top'/'bottom' display layer, whereas the pads for THT components are on the 'pads' layer. Why is this? I have ...
4
votes
2answers
829 views

Minimum solder mask ridge (sliver) for DFN package?

What is better: No solder mask at all under the fine pitch component with thermal pad or shrink the thermal pad to leave room for a solder mask ridge around the thermal pad? I am making the layout ...
1
vote
2answers
1k views

pcb damaged, broken copper any ideas?

I was trying to solder a new capacitor on my pcb and I had problems. At the end I think I burned the copper under the pcb mask and I am wondering if i totally destroyed my pcb. Here is a picture: ...
7
votes
1answer
224 views

Solder Mask on fPCB starting to degrade

I have a flex-PCB that is acting as a sensor bus for one of my projects. I started getting some wonky readings from one of the sensors, but I found that if I removed the sensor from the bus (with ...
6
votes
1answer
218 views

What effect does using two different forms of solder mask on the same PWB have?

We found some PWBs that seem to have both film and liquid solder mask applied on the board. I have never encountered this before and was curious to see if this is acceptable for use.
6
votes
3answers
3k views

Questions on mass-production soldering

Wave soldering I am trying to understand how wave soldering works. Unfortunately the Wikipedia article has has left me unsure about the process: Is the entire board with its components ...
6
votes
1answer
569 views

Will “hot plate” reflow soldering work without a solder resist coating?

With a successful through-hole design under my belt I am now ready to try fabricating a board that uses surface-mount components. I have been reading about this, and have gathered that the DIY crowd ...
3
votes
1answer
4k views

DIY solder mask + toner transfer

so I've gotten a decent 1 layer toner transfer process down and I'm looking to add some nice touches to it before I move on to trying 2 layer boards. Anybody know how to do a nice silkscreen layer or ...
13
votes
5answers
9k views

What is the purpose of solder mask expansion?

I see recommendations of 2-4 mils for solder mask expansion. But why is it necessary?
7
votes
5answers
4k views

Soldermask at home?

I am interested in putting that nice green / red soldermask on the PCBs that I make at home. The problem is I can't find a lot of information on it, like where to buy it, etc. Do any hobbyists ...