There is a reason for USB-C extensions not to be part of the standard. They can be bothersome in the best case and dangerous in the worst.

  • ggtdbz@lemmy.dbzer0.com
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    3 days ago

    I wish there was a clearer explanation or nomenclature for this. With things like cables and converters everything always seems to have a black box layer.

    I don’t understand why there are so many PD profiles either. Maybe Cat-1 USB-C, Cat-2 USB-C, etc? Maybe just having a smaller set of voltage-defined profiles that have a safe maximum current rating? Maybe that’s already how it is? I don’t know

    • Anivia@feddit.org
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      3 days ago

      There are technical reasons for why so many PD profiles exist.

      In fact they were not enough, which is why the USB Standard was extended with the “PPS” extension recently, which let’s the attached device freely choose a voltage between 3V and 21V in steps of 20mv, and more importantly it let’s the device freely change this voltage without interrupting the charge process. This change makes it possible for devices to bypass their own but in charging electronics and just directly forward the voltage coming from the charger to the device, improving efficiency and significantly decreasing how much the device hears up during charging

      Sadly PPS is not found on many devices or chargers yet, and makes the already complicated USB C charging situation even more complicated for consumers

      • barsoap@lemm.ee
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        3 days ago

        charging electronics and just directly forward the voltage coming from the charger to the device

        I am highly sceptical of anything that would connect USB voltage, no matter how finely negotiated, directly to the battery terminals. Finely tunable voltage over USB is useful for keeping the buck/boost converter on the device side small, though, or just efficient because it doesn’t have to do as much work. If you can charge over standard PD extending to charging over PPS should only be a software change as your hardware is already more than capable.