An ASIC is an integrated circuit.
There might be a new type of technology in the future that makes integrated circuits obsolete
For example, right now there are 3DICs, which is a new type of IC, and I don't think most Bitcoin miner ASICs are 3DICs at the moment.
Then in the future there could be a new type of invention that is even more efficient than ICs.
Ok, it's final step for pure digital electronics.
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