I've a few designs where I need footprints on the PCB for non-electronic components i.e. logos, LED light pipes, etc.
My current practice is to create a component for these with a schematic symbol and footprint then add them to the schematic.
I've always wondered if this is normal practice? It makes my schematics look untidy, mostly because I need to adopt a standard design for these non-electronic schematic symbols. They're all sorts of shapes and sizes but that's a different problem
I'm just wondering if there's an industry standard approach to this i.e. have them on the schematic or just add them to the PCB manually?
It depends on the CAD tool you are using as to just what you can do along those lines. Back in the old days when I was drawing schematics with plastic lead on mylar (just after the ink on vellum days!), one of my favorite things to put on a schematic was a "cloud" (or multiple "clouds") that I would put information in like address decoding, expected waveform, expected voltage etc. Made troubleshooting a lot easier to have that information available looking at the schematic. Early days of CAD made it really tough to add that information and it was a pain when you have a scope probe in one hand, adjust the scope with the other and still trying to look at the schematic and find the info on what to expect there.
I'm just wondering if there's an industry standard approach to this i.e. have them on the schematic or just add them to the PCB manually?
I'd say add them to the PCB manually.
It's normally an electrical schematic and about the only time I've seen anything mechanical on a schematic is if it's something like an optical disc on a motor shaft showing what's "triggering" the optical interrupter, etc.
It is common to have notes or tables on schematics. (For example a table showing jumper or switch settings for the default configuration (or various configurations/options), or a note saying how to adjust a pot, etc.)
I've seen mechanical schematics (and maybe I've seen optical schematics) but those are separate diagrams showing how those systems work.
With Eagle, where virtually everything that's on the PCB must be on the schematic, I create a schematic symbol that's just text. For example, the PCB outline that fits a specific box appears on the schematic as "Use box." A logo will just have the symbol say the name of the logo. A light pipe might be "Use light pipe part #..."
One place I worked at had everything on the schematic, like holes. This was so that they could be electrically connected, or not, to ground. Also the hole showed up on the parts list as a screw so that everything on the PCB was included on the BOM ( Bill Of Materials).
