Juan,
Well you could look at IPC 2221 which has some info about that, or actually IPC spec IPC-D-325 will have more
However if part body is big enough to fit large enough text for readability
in the size document you are printing, Ref Des should be inside body of part for assembly dwg.
Where parts are too small I usually put them as close as possible to where they are placed in silkscreen. Example SOT-23
This helps in inspection etc.
Any silkscreen must be visible when part is installed though.

-----Original Message-----
From: DesignerCouncil [mailto:[log in to unmask]] On Behalf Of Juan Vega
Sent: Tuesday, April 01, 2014 12:38 PM
To: [log in to unmask]
Subject: [DC] Assembly standard + best practices

Hello,
Can someone help me pointing out which standard should I consult in order to do a Printed circuit board assembly drawing?
I am trying to find, which is the best practice for location of reference designators (inside the part drawing, outside).

Best regards!!

Juan Vega | Product Enngineer | Branson Ultrasonics Emerson Industrial Automation | Lote #4 Carretera Nacional KM 8.5 Modulo Industrial America | Nuevo Laredo| Tamaulipas | 88277 | Mexico T + 011 52 867 711 0821 | F + 011 52 867 711 0811 [log in to unmask]<mailto:[log in to unmask]>



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