CTI respected in footprints?

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   Hi,
question to librarians mostly.
Do you respect CTI requirements in designed footprints?
Lastly I had a discussion in my organization about CTI for our products. 
We mostly use CTI 400 for laminate, but silkscreen legend has CTI 175. This reduces the allowed electrical distance between two potentials on the board.
A good example is electrolytic capacitor, where entire negative side is covered with silkscreen.
Did you ever investigated such case?

Are you libraries common and PCB designers apply adjustments, or you design them specifically for plenty of requirements ?

I asked the question: when buying tiles for your new bathroom, do you expect getting ones with already cut holes for your water outlets or you drill it depends on needs at construction side? Silence as an answer.

What's your company's approach? 

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StachowJ Members Profile Send Private Message Find Members Posts Add to Buddy List New User Joined: 17 Oct 2018 Status: Offline Points: 7	Post Options Post Reply Quote StachowJ Report Post Thanks(0) Quote Reply Topic: CTI respected in footprints? Posted: 20 May 2022 at 4:27am
	Hi, question to librarians mostly. Do you respect CTI requirements in designed footprints? Lastly I had a discussion in my organization about CTI for our products. We mostly use CTI 400 for laminate, but silkscreen legend has CTI 175. This reduces the allowed electrical distance between two potentials on the board. A good example is electrolytic capacitor, where entire negative side is covered with silkscreen. Did you ever investigated such case? Are you libraries common and PCB designers apply adjustments, or you design them specifically for plenty of requirements ? I asked the question: when buying tiles for your new bathroom, do you expect getting ones with already cut holes for your water outlets or you drill it depends on needs at construction side? Silence as an answer. What's your company's approach?



Tom H Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Joined: 05 Jan 2012 Location: San Diego, CA Status: Offline Points: 5719	Post Options Post Reply Quote Tom H Report Post Thanks(0) Quote Reply Posted: 20 May 2022 at 8:14am
	CTI has never been a consideration in land pattern (footprint) requirements in any IPC Standards. What is PCB CTI? - Printed Circuit Board Manufacturing & PCB Assembly - RayMing (raypcb.com)
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StachowJ Members Profile Send Private Message Find Members Posts Add to Buddy List New User Joined: 17 Oct 2018 Status: Offline Points: 7	Post Options Post Reply Quote StachowJ Report Post Thanks(0) Quote Reply Posted: 23 May 2022 at 2:04am
	Thanks Tom, Anyway, does someone consider CTI on the library level? What's your general approach guys? Do you maintain it on PCB design level, or you implement it in the library? Do you think is a good approach? I am pushed to redesign my footprints according CTI requirements (like modify silkscreen legend from ElCap (negative pin marking).