Can anyone show us the technical design of an ASIC appropriate for Equihash/Ethash?
I doubt it. Ethash was designed (please
/lcybzq6]read the design paper) to require huge memory bandwidth.
ASICs give you advantage in SHA Hashes/Watt ratio, but for Ethash that represents a small fraction of the process (unlike the Bitcoin, that, essentially, IS a SHA).
In other words, ASICs can give you cheap SHA rounds but can't provide you enough memory. You have to have 1GB dataset per ASIC.
Technically you can regenerate parts of the dataset as you go - but that is going to kill the performance (+16MB ASICs aren't cheap).
It is still doable in ASICs - however not economical.