TRRS cable layout

[Anonymous No.2537958]

Ok /diy/, I asked /g/ for advice and it turns out they're a bunch of posers who don't understand consumer electronics, so I'm coming to you for advice on picrel project I am ready to start soldering.

Basically, I need 5v DC, one analog video channel, and one audio channel. Please correct me if I'm wrong, but this means I need 4 wires because they can share ground? In that case, I have decided to use 3.5mm TRRS (because it is analog AV and meets size constraints), which I would like to be compatible with existing products also using this connector. The problem is that every major company seems to have implemented their own version. Worse, constant voltage destroys speakers, so I need to be very careful which pin is +5v.

>I would like to be able to plug in normal headphones (with mic or otherwise) to listen to the single channel of audio without destroying them, or at the very least without creating a short circuit.
>I would also like to be able to plug in my NTC CHIP which has its own TRRS that is laid out LRGV.
>I would also like to plug in a Samsung TV, which uses the layout VRLG.
>All else being equal, it feels right to me to have the sleeve be ground and tip be +5v.

Based on these goals, what do you think is the best layout? Also, will 5v destroy a headphone mic? Will an analog video signal do the same to a headphone speaker?

My project aside, which TRRS standard should rule them all?

[Anonymous No.2537964]

>>2537958
I have no idea what you're talking about but I wanted to post this picture.

[Anonymous No.2537969]

found this.

No matter what, I'd recommend not enabling that 5VDC to be sent through the cable until the jack is fully inserted. A lot of jacks include a sensing pin that you can use to keep the jack electrically isolated until fully connected.

[Anonymous No.2537981]

>>2537969
Good catch, I hadn't considered the connections it might make while inserting. I wonder if this could be fixed by making 5v the sleeve, so last inserted?
>sensing pin
Makes sense, but my cheapo jacks def do not have this, and I'm not able to find anything about it by searching

[Anonymous No.2537983]

>>2537981
Search for barrel connectors on digikey with "internal switches." You really only need a tip switch.

[Anonymous No.2538720]

If you are using different layouts you would need some kind of switch to reconfigure the plug or it wouldnt be compatible interchangeably.

[Anonymous No.2538873]

what about something like this? or one of those midi connectors

[Anonymous No.2538883]

>>2538873
Ive used these before.
Soldering them makes you want to kill yourself.

[Anonymous No.2539069]

>>2538883
>so what changes

but honestly, I'd much rather solder a din-plug than a minijack. maybe yours were corroded?

[Anonymous No.2539112]

>>2538883
>Soldering them makes you want to kill yourself.
Tell me you don't use flux with out telling me you don't use flux.

[Anonymous No.2539156]

>>2537958
I wouldn't recommend to do all that, because you are mixing signals from different circuits
>short circuit
most likely
>Also, will 5v destroy a headphone mic?
>noise
>induction
but whatever, check the nominal power of your headphones, if your source is sending too much, you can be shure. And it can fuck all the data since you are mixing mV with Volts.
>Will an analog video signal do the same to a headphone speaker?
The same

Also, there is two main issues, the noise can distort enough to render the signals noise or simply imagine hearing hisses,scratch or an analog tv with no channel to a level enough to have you deaf at least for a moment and if the designs are well protected you can blow certain parts of your devices, having no sound or vid.
>proceed with xtreme caution
at least the 5v take it in a line apart.

[Anonymous No.2539320]

>>2538720
This is a great idea. Do multiplexed switches exist or do I need to make one mechanically or from transistors?
>>2538873
I did consider those "aviation" cables or whatever they're called, but rejected them because they're too clunky for my wearable application
>>2539156
What noise? Does what you're talking about have anything to do with sharing ground, because I'm still confused about the implications of that

The good news is that it works. I ended up just bending the pins and soldering the jack directly to my board in a way that makes 5v the last to be inserted