Making components and patterns in Diptrace where should the origin go?

[steve_w]

Just a minor point, when making schematic symbols and patterns is there a convention of where to have the x y axis (0,0) point?  I.e. in the center or at the say the bottom left corner (so all the co-ordinates are positive)?

Is there a convention or standard to comply with?  (I dont think AS1100 covers this ? dont have a copy since I retired)

I have experimented and it doesn't seem to matter to Diptrace.

regards

Steve W

[DerekG]

Most people place the origin of the schematic on the bottom LHS corner - just convention (like when you are reading a graph).

When making new components, make sure you place the origin at the centre of the PCB footprint in the library as this helps with SMD robot loading.

Diptrace will do this easily for you when laying out new components in the Pattern Editor. Once you have finished making the new footprint select:

Edit>Center Pattern

[steve_w]

Ta Derek

regards

SW

[Sirius631]

Hi,

I haven't used DIPTrace yet, although I've decided to download it after seeing Dave's first look video. I've only had my hands on the first PC based schematic planners and autorouters in the late '80s.

What occurred to me back then was that when creating component symbols, no matter where the origin was, the pads should be drawn on the intended snap grid to ensure ease of connecting wires when creating the schematic layout.

Sorry if this is a dumb suggestion which doesn't need saying.

[zapta]

I place the origin where it will be the easiest to enter the coordinations of the pads. Sometimes it's in the center (leveraging on symmetry) and sometimes it's in one of the corner (e.g. for 0.1" DIP grid).  It' doesn't matter much except when rotating the part in the layout.  (I am a Eagle user but I presume the considerations are similar).

[steve_w]

Thanks guys,

I just wasn't sure.

you wont be disappointed with diptrace Sirius, I have no experience in PCB design but picked it up OK, just got my first board back from Dirty PCBs,

check it out

[Simon]

There is one consideration to make. If you intend to use 3-D models of components then censoring the origin on the footprint makes a lot of sense particularly if you will have to manually coordinate placement of the 3-D model.