[angusgr]

(Blog author here)

You're spot on about the PLL stage, a few people on Reddit pointed the same thing out when I first posted it. Makes sense, although I still think it's interesting they added it internally to an otherwise (apparently) cloned design.

You're also right that USB CDC does provide the option for a generic USB Ethernet device, however this silicon is ASIX-specific (not just the USB IDs.) ASIX's Windows drivers include their own system driver binaries, and the ASIX Linux driver has a lot of ASIX-specific stuff in it.

I think it's kind of possible ASIX made this themselves as some kind of no-name branded unadvertised market segmentation effort. I can't understand what their rationale would be exactly but hardware companies do unusual things sometimes...

[userbinator]

If you go only on the definition of a clone being "compatible interface", then there are tons of other examples of that in the electronics industry - it's more commonly known for simpler parts like voltage regulators (how many companies make a '7805?), opamps, transistors, etc. but also occurs with more complex ones too.

IC companies make unadvertised products all the time, for anyone who is willing to buy enough... look at Apple's Lightning cable and TI's BQ2025, for instance.