How do I remove solder mask from a pad (touch sense pad)

[orbeet]

Hi All,

I am trying to create a touch sense pad which needs to have the pad fully covered in resist (no solder mask around it) but Diptrace doesn't give me any options to remove solder mask during the creation of such touch sense pad in the pattern editor (single pin pad - rectangle). I tried right clicking on pad and selecting 'Paste / Mask Settings...' and setting the top solder mask to open, tented, all of them but the mask persists.

The issue is that I need to connect this touch sense pad directly to an MCU pin (single pin to pad connection) and the only way to get a net out to such a touch sense pad is if the pad has a pin assigned to it - otherwise I would just create a solder fill (with resist covering fill geometry) and connect my MCU pin signal directly but it will not allow me to do this.

Please help!

O

[Tomg]

The "Renew Layout from Schematic" (By Components) tool in the PCB Layout editor will not change the mask/paste settings of the original component. The developers intentionally set it up this way in order to preserve the original mask/paste settings. You will have to manually change the mask/paste settings in the PCB Layout editor and resave the layout. Once that has been accomplished, the PCB layout will remember the new settings.

Another method would be to place another component from the updated library nearby, disconnect the traces from the original (right-click on it and select Disconnect Traces), delete it, move the updated component into the same location, connect the traces (right-click on it and select Connect Traces) and change the reference designator to match that of the original component.

[orbeet]

Hi Tom,

Thanks for the prompt response. However, you did not answer my question. I need to know if there's a way to remove the solder mask from a single pin pad in layout editor. So far, I tried everything and no method allows for the removal of solder mask from a pad geometry.

Appreciate the support,
O

[Tomg]

Oh. Did you set the "Apply to:" drop-list to "Current Pad"?

[orbeet]

Hi Tom,

I tried applying to current pad to no avail. I set mask to 'open' and paste to 'no solder' in layout editor, saved it then went to PCB editor and on my board I dropped in this touch sensor pad with new settings but mask (in blue outline) is still there. I was going to post images of the mask setting dialog box and the pad on my board layout but I don't see how to attach an image. It's asking for url of the image, all I have is jpegs.

O

[Tomg]

I'm assuming you need the mask to cover the pad. If so, select "Tented". Just in case you were not aware, when manually "adding" solder mask in DipTrace you are actually manually adding an opening in the automatically-created solder mask.

When adding an image to a post, I have always had success using the [Attachments] tab below the text editor.

[orbeet]

Thank you so much, Tom. This works now!
Always a pleasure getting support from you.
O