"different pins get shorted together"

But phone connectors have built-in switches, so I would think there must be some configuration to route the powered lines through the switches so that the power is only connected until the plug is fully inserted, I think. For instance, if insertion of the tip control a double-pole double-throw switch, then one of those could route the ground pin and one could route the power pin, such that those power lines are only routed once full insertion has been made.

> The hobbyist ergonomic keyboard community has used TRRS for the link between the left and right half of the keyboard for a while now, and it routinely causes issue due to people accidentally unplugging it while powered - which fries their keyboard.

I believe that someone has had this problem, but I cannot replicate it. I unplug the right hand of my Iris all the time like a jackass and so far no ill effects. IDGI.

It depends a lot on the exact pinout used by the individual keyboard, and which side you disconnect first. I'm active in a community dedicated to keyboards like these, and I think we see someone with a dead keeb due to it once a week or so.

Huh, how bout that. What models see it? I’d be interested to see what they’re doing vs what the Let’s Split and Iris do.

Can anyone explain why Toslink is on almost every consumer AV product circuit board?

I love Toslink but I wouldn’t expect it on as many TVs, devices and systems as I see them

Is it just the lack of the need for DAC chips, cost, or something I’m missing?

Many TVs and devices exclude many digital and analogue sockets, but for some reason I always see Toslink

There are a few big reasons to prefer TOSLINK over other digital interfaces:

Cost: TOSLINK can be implemented with two plastic connectors (one an LED, one a photodiode). After that, you're in a 3.3V domain. Other interfaces require transformers and other analog electronics to go from the signalling domain to one that is useful in a digital system.

Noise/electrical performance: Using an optical interface means the systems are fully electrically isolated, with no risk of ground loops or noise coupling. There is also no risk of radiated emissions.

Cabling convenience: TOSLINK supports a very long, thin, cable that can be checked for functionality at a glance (look at the receiver end: is there light?). Any comparable electrical interface is going to be at least 3 conductors and require a multimeter to check for breaks.

Lastly, the reason to prefer digital is that every A/D-D/A step adds noise, distortion, and latency. The general desire is to convert to analog as late in the chain as possible to avoid that.

TOSLINK is seriously underrated

Then we need light to transfer power too, sounds slightly unsafe for eyes, maybe.

Not necessarily. You could design the plug like "copper tip, plastic ring, copper sleeve". With the right dimensions the contacts aren't shorted together during insertion.

Alternatively, use a ring which is segmented in 120 degree pieces, and place two contacts 180 degree apart in the socket: any two ring segments might be shorted, but never all three - and there will always be at least two segments with a connection. Use a bridge rectifier to get a fixed polarity out of it.