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BaseJump Open-Source Hardware Accelerator Motherboards
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Real Trouble Through-Hole Plating #5

Closed abeyene closed 1 year ago

abeyene commented 2 years ago

Hi,

I've received a query from my PCB manufacturer about whether a particular through-hole on Real Trouble is plated or not. A copper pad exists in the copper layer but a table description for the symbol describes the hole as non-plated (see the below photo). Which is correct? Thanks.

RealTroubleThroughHole

taylor-bsg commented 2 years ago

@gaozihou

gaozihou commented 2 years ago

@abeyene Thanks for your question! This should be a plated through hole (PTH), so the table is incorrect.. Sorry for the inconvenience caused!

cmcjames commented 2 years ago

Paul-

Isn’t that the FMC connector’s keying hole?

The SAMTEC datasheet’s recommended PCB layout section for an FMC connector shows the keying hole as 50 [1.27] NPTH.
In the VITA 57.1 standard “Rule 3.25: All keying holes shall remain electrically isolated from the mezzanine module’s circuit ground.”

I assume it doesn’t matter as the key is likely some kind of plastic.

What is the reasoning for it being a PTH? Am I missing something?

-james

From: Paul Gao @.> Sent: Tuesday, February 22, 2022 8:30 PM To: bespoke-silicon-group/bsg_motherboards @.> Cc: Subscribed @.***> Subject: Re: [bespoke-silicon-group/bsg_motherboards] Real Trouble Through-Hole Plating (Issue #5)

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@abeyenehttps://github.com/abeyene Thanks for your question! This should be a plated through hole (PTH), so the table is incorrect.. Sorry for the inconvenience caused!

— Reply to this email directly, view it on GitHubhttps://github.com/bespoke-silicon-group/bsg_motherboards/issues/5#issuecomment-1048372881, or unsubscribehttps://github.com/notifications/unsubscribe-auth/ABJCDXUGSFDIOIHBUEM3TATU4Q2BZANCNFSM5PCZQP7Q. Triage notifications on the go with GitHub Mobile for iOShttps://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675 or Androidhttps://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub. You are receiving this because you are subscribed to this thread.Message ID: @.**@.>>

gaozihou commented 2 years ago

Thanks @cmcjames!

Yes you are right, Samtec datasheet suggests 1.27 NPTH for those keying holes, so it is totally fine to go with NPTH.

I suggested PTH because

Again sorry for the confusions caused!

cmcjames commented 2 years ago

Thank you. No worries!

-james.

From: Paul Gao @.> Sent: Wednesday, February 23, 2022 12:54 PM To: bespoke-silicon-group/bsg_motherboards @.> Cc: James Millar @.>; Mention @.> Subject: Re: [bespoke-silicon-group/bsg_motherboards] Real Trouble Through-Hole Plating (Issue #5)

[EXTERNAL EMAIL] DO NOT CLICK unless you know the content is safe..

Thanks @cmcjameshttps://github.com/cmcjames!

Yes you are right, Samtec datasheet suggests 1.27 NPTH for those keying holes, so it is totally fine to go with NPTH.

I suggested PTH because

Again sorry for the confusions caused!

— Reply to this email directly, view it on GitHubhttps://github.com/bespoke-silicon-group/bsg_motherboards/issues/5#issuecomment-1049051862, or unsubscribehttps://github.com/notifications/unsubscribe-auth/ABJCDXVVH6C4FVFWH2HB34TU4UNMPANCNFSM5PCZQP7Q. Triage notifications on the go with GitHub Mobile for iOShttps://apps.apple.com/app/apple-store/id1477376905?ct=notification-email&mt=8&pt=524675 or Androidhttps://play.google.com/store/apps/details?id=com.github.android&referrer=utm_campaign%3Dnotification-email%26utm_medium%3Demail%26utm_source%3Dgithub. You are receiving this because you were mentioned.Message ID: @.**@.>>

abeyene commented 2 years ago

Thanks for the clarification @gaozihou @taylor-bsg