Nicholas:
clearances are also for mechanical features to keep them from shorting
out traces or smashing components. these are basically common sense I.E.
does it fit.  clearances are also specified to prevent one part of a
circuit from interfering with another like an AC MAINS circuit
interfering with a low level audio circuit.  UL and IEC requirements
demand specific minimum clearances to separate circuits for safety
reasons.

> -----Original Message-----
> From: TPE Engineering TechNet [SMTP:[log in to unmask]]
> Sent: Thursday, August 26, 1999 7:54 AM
> To:   [log in to unmask]
> Subject:      Re: [TN] What is clearance -Reply -Reply
>
> Nicholas,
> If the clearances were not there, you would have every layer
> shorted to each other.. Clearances are used to insure that
> any specific power or ground plane will not short to any
> other layer. The only time a clearance will not be there is
> when it is desired for that hole (net) to make a connection to
> that plane.
> Ron
>
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