USB-C is an unfixable mess, that I’m convinced of, but a small part of me saw light at the end of the tunnel — that was until Apple launched the iPhone 17 series. With Apple’s latest phones, it’s now even harder for consumers to find the perfect plug to optimally fast-charge all their gadgets at once. Allow me to explain why.
The good news, as it were, is that the iPhone 17 series claims “up to 50% charge in 20 minutes” with Apple’s new 40W Dynamic Power Adapter. That’s still not super fast, but it is undoubtedly an improvement on last year’s models, which ended up at around 40% after the same length of time.
I don’t have an iPhone 17 to test the specifics yet, but the secret to slightly faster charging this year appears to be the introduction of USB Power Delivery Adjustable Voltage Supply (AVS). The bad news is that Apple still has not adopted the widely supported USB Power Delivery Programmable Power Supply (PPS) protocol used by essentially every flagship Android phone, but at least it’s not added another proprietary model into the mix. Unfortunately, you’ll be hard-pressed to find support for both protocols on popular USB-C chargers — at least for now.
USB Power Delivery, PSS, and now AVS. Anyone guess what the differences are?
Apple has a new 40W Dynamic Power Adapter to sell you, but it’s not the only charger that supports AVS; Google’s new 67W Pixel Flex charger does too. Apple’s new charger can hit 60W temporarily with a current boost, but it’s doubtful the latest iPhone will sustain power that high. Either way, Apple’s charger does not appear to support PPS — making it far less helpful if you’re a cross-platform gadget owner.
Likewise, the countless high-end PPS chargers I’ve tested don’t support AVS, owing to its relatively new status. Options are extremely limited if you want to charge the latest iPhones and Pixel as quickly as possible. PPS was introduced in the USB PD 3.0 specification, while AVS was added in 3.1. With USB PD 3.2, AVS became mandatory for Standard Power Range (27–100 W) and was always required for Extended Power Range (>100 W) — making it compulsory for Apple’s 30W+ power rating on the latest version of the standard.
What is USB Power Delivery AVS?
Robert Triggs / Android Authority
The key takeaway is that newer high-power devices implementing the latest USB PD 3.2 specification must support AVS, but PPS remains optional. Apple’s adoption of AVS with the iPhone 17 is likely due to following this official requirement rather than the brand actively supporting the best fast charging option available for iPhones — which would still be PPS.
If you’re interested in the technical differences, AVS enables voltage selection with enhanced 100mV accuracy and scales from 9V to 20V for SPR devices (phones, tablets, laptops) and up to 48V for HPR/EPR. By comparison, PPS provides finer 20 mV voltage steps (with 50mA current steps) up to 100W for SPR gadgets. In earlier revisions, PPS could go as low as 3.0V (later 3.3V), but in the current USB PD 3.2 spec, its minimum appears to have been raised to 5V, with a typical usable range up to 21V.
... continue reading