new kind of parts...

[John Larkin]

I was thinking of creating a few new parts in our schematic library,
like BOX and BOX/1Lead and BOX/2Lead maybe. Each will be just a box on
the schematic and not have a layout decal. The leads allow the object
to be grounded or whatever.

The idea is that I can use them for heat sinks, tie-downs, even the
bare PCB itself, things that would not usually be on the schematic but
we want to remember to put on the BOM.

 

[Lasse Langwadt Christensen]

fredag den 23. juni 2023 kl. 20.51.19 UTC+2 skrev John Larkin:

I was thinking of creating a few new parts in our schematic library,
like BOX and BOX/1Lead and BOX/2Lead maybe. Each will be just a box on
the schematic and not have a layout decal. The leads allow the object
to be grounded or whatever.

The idea is that I can use them for heat sinks, tie-downs, even the
bare PCB itself, things that would not usually be on the schematic but
we want to remember to put on the BOM.

maybe a question of terminology, but in my mind BOX is just a schematic symbol

the \"part\", say a tie-down would be the partnumber, description, etc. that get in the BOM
and that is uses the schematic symbol box all in the parts database

would you just plop down a BOX and manually fill out the properties without creating the part in your parts database?

 

[John Larkin]

On Fri, 23 Jun 2023 13:10:33 -0700 (PDT), Lasse Langwadt Christensen
<langwadt@fonz.dk> wrote:

fredag den 23. juni 2023 kl. 20.51.19 UTC+2 skrev John Larkin:
I was thinking of creating a few new parts in our schematic library,
like BOX and BOX/1Lead and BOX/2Lead maybe. Each will be just a box on
the schematic and not have a layout decal. The leads allow the object
to be grounded or whatever.

The idea is that I can use them for heat sinks, tie-downs, even the
bare PCB itself, things that would not usually be on the schematic but
we want to remember to put on the BOM.

maybe a question of terminology, but in my mind BOX is just a schematic symbol

Yes, it would be a visible dummy schematic symbol, but would have the
attributes that cause a part on the schematic to appear in the BOM.

the \"part\", say a tie-down would be the partnumber, description, etc. that get in the BOM
and that is uses the schematic symbol box all in the parts database

would you just plop down a BOX and manually fill out the properties without creating the part in your parts database?

One attribute of any part is its MAX number, namely the stock number
in our material control system. When we buy a part, we create a bin
and assign a 7-digit stock number and declare the manufacturer(s) and
their part numbers that are acceptable buys. Every part on a schematic
has a MAX number attribute, and the schematic generates the BOM. But
we have been manually adding the non-electronic parts, like the PCB
itself!, to the BOM and that\'s a nuisance, especially for board revs.
I thought it would be cool to put the non-electronic parts on the
schematic too.

We already have schematic symbols for a few sizes of screw holes, like
for mounting screws and scope grounds, but they don\'t include the
screws themselves.

What do other people do about adding non-schematic parts to the BOM of
a PC board?

 

[Joe Gwinn]

On Fri, 23 Jun 2023 15:09:57 -0700, John Larkin
<jlarkin@highlandSNIPMEtechnology.com> wrote:

On Fri, 23 Jun 2023 13:10:33 -0700 (PDT), Lasse Langwadt Christensen
langwadt@fonz.dk> wrote:

fredag den 23. juni 2023 kl. 20.51.19 UTC+2 skrev John Larkin:
I was thinking of creating a few new parts in our schematic library,
like BOX and BOX/1Lead and BOX/2Lead maybe. Each will be just a box on
the schematic and not have a layout decal. The leads allow the object
to be grounded or whatever.

The idea is that I can use them for heat sinks, tie-downs, even the
bare PCB itself, things that would not usually be on the schematic but
we want to remember to put on the BOM.

maybe a question of terminology, but in my mind BOX is just a schematic symbol

Yes, it would be a visible dummy schematic symbol, but would have the
attributes that cause a part on the schematic to appear in the BOM.


the \"part\", say a tie-down would be the partnumber, description, etc. that get in the BOM
and that is uses the schematic symbol box all in the parts database

would you just plop down a BOX and manually fill out the properties without creating the part in your parts database?

One attribute of any part is its MAX number, namely the stock number
in our material control system. When we buy a part, we create a bin
and assign a 7-digit stock number and declare the manufacturer(s) and
their part numbers that are acceptable buys. Every part on a schematic
has a MAX number attribute, and the schematic generates the BOM. But
we have been manually adding the non-electronic parts, like the PCB
itself!, to the BOM and that\'s a nuisance, especially for board revs.
I thought it would be cool to put the non-electronic parts on the
schematic too.

We already have schematic symbols for a few sizes of screw holes, like
for mounting screws and scope grounds, but they don\'t include the
screws themselves.

What do other people do about adding non-schematic parts to the BOM of
a PC board?

Have a separate mechanical diagram for the PCB assembly, et al. In
some cases, the core drawing number is the same, and different
three-letter prefixes differentiate PCB schematic from PCB mechanical
design. And there is a document tree (itself a drawing) that defines
how it all fits together.

Part of the reason for this is that schematics use one set of
electronic design tools, and mechanical assemblies a different tool,
and so on.

Joe Gwinn