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0 pointsmaven292y ago0 comments

The USB standard has provision for analog output through the MUX, and all compliant MUX/controller chips will have implemented this.

https://www.anandtech.com/show/10719/usbif-publishes-audio-o...

If this is so non-trivial, Chinese OEMs like Huawei have in fact succeeded in analog output. This is despite the fact that their receptacles are on a 50mm long flex PCB, you don't need another 2 signal layers or an extra daughterboard.

The laws of physics are the same everywhere across the world. Just because Apple is incompetent, it does not imply everyone else is.

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Kirby642y ago

You're talking to someone who works with folks on the USB-IF committee. Analog output through the DP/DN/SBU pins is not standard these days. A mux isn't even necessary in many implementations. Also, this functionality in USB Type-C is straight up deprecated. Just because it's technically possible (and sure, I agree, it is technically possible) doesn't mean it isn't more costly, less efficient, and wasteful vs. just putting the codec directly in the USB-C to 3.5mm dongle.

Here's the rationale than USB-IF gave in the ECN:

>> Few hosts support analog audio accessory. Those that might could be confused when connected to a device supporting corrosion mitigation, but no detrimental behavior should be seen. This should be a corner case of a corner case so likely zero to very low ppm of this condition. Note, any compliant host that supports analog audio accessory today is also required to support digital audio accessories, so there should be no impact to users."

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