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I am currently working on a project that goes over multiple PCBs for the first time and realised that i don't know what the "standard" or best practice for component designators over two (or more) boards. Do designators start over on each board, do they have like an earlier designator (i.e. board one R001- R099, board two R101-R199, etc)?

The boards are going to be panelized and sent off to a pick and place in china, so how would it work if you had two boards with designators that start again?

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    \$\begingroup\$ To me it makes more sense to adopt a numbering scheme based on the schematic. For example R1XX for resistors on sheet 1 and so on. That way it's easier to find a part on the schematic. For the other way around, finding parts on the board, there should be some kind of layout grid bundled with the scematics that lists the components and their location on the grid. That's what I often see in good service manuals and it works well. \$\endgroup\$ – Unimportant Dec 29 '18 at 13:38
  • \$\begingroup\$ It is good to see that you are thinking about this issue: congratulations on making the leap of imagination, rather than completing the project before noting the documentation issues. Clarity in reading the schematics is probably best served by NOT reusing any component designation across the whole project. \$\endgroup\$ – Whit3rd Dec 29 '18 at 21:52
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I had worked on similar kind of project before having 3 boards that are interconnected.

Even though 3 boards... as far as schematic conserned we usually make a common schematic file.. with sections

So going with continuous designation is good.

I feel this way comfortable.

The boards are going to be panelized and sent off to a pick and place in china, so how would it work if you had two boards with designators that start again?

It is also not a problem with pick and place machine what ever your approach.

But going with continuous designation approach is better for BOM management(inventory), Diagnosis etc. Since in every case you need to consider any component with the whole schematic. it leads to less confusion.

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  • \$\begingroup\$ Yeh.. actually for every board we will design separate schematics but we have to make one master schematic and interconnection drawing for overall solution. At that stage continuous thing will be useful. but it's up to you. \$\endgroup\$ – Satish Singupuram Dec 29 '18 at 15:27
  • \$\begingroup\$ Then I understand the continuous way. Though I'm not sure if I understand the need for the master schematic, but if that works for you, I guess it is fine. We present all the boards only on block diagram level. \$\endgroup\$ – TemeV Dec 29 '18 at 16:03
  • \$\begingroup\$ Ok got it. It's up to you. \$\endgroup\$ – Satish Singupuram Dec 29 '18 at 20:50
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I consider a board to be single entity as a part of a device. All the boards have their own schematics and the reference designators start over for each board.

In production the boards must be anyway in their own panels they have own BOM's etc. so it doesn't matter what the reference designators are. Use any convention that fits well to your design flow.

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