Tools used to manufacture entire digital systems
are my assertions above correct?


Everything you have written above that line is correct.

This is a multipart question. At the very top system level, you will find surprisingly heavy use of Word and Visio to produce a series of block diagrams. The different specialisations will then be handed off to different teams using individual tools.

Designing a whole new product out of new parts in one go with no prototypes is a risky endeavour. Generally you'd do it in stages: sort the custom ASIC out before finalising the motherboards.

RAM is highly structured and I think the tools for this may be proprietary things that just emit GDSII. Individual RAM cells can be simulated in SPICE.

The final question depends slightly on what you're making, but last time I did it I sent:


a PCB stackup: set of Gerber files with list of drill holes and thickness/finish (ENIG, soldermask colour, etc)
a placement list (autogenerated from the PCB software, used for pick-and-place)
a Bill of Materials (BOM) which is a spreadsheet of parts by part designator
a test plan for checking the PCBs (Word document with pictures)
software binaries to be preloaded into the microcontroller (Microchip BIN format)
assembly diagrams for how to put the PCB in the case, fit buttons etc.


Injection moulded casework was designed in Solidworks and commissioned seperately. If you need things which can't be reflow soldered that involves extra explaining.