For the past few years, a number of smartphones have offered so-called “fast charging” solutions. These options are meant to charge the device rapidly (Qualcomm’s Quick Charge 3.0 is one such example).
Earlier this year, we discussed how USB-C and QuickCharge 3.0 were incompatible, thanks to their different requirements for device voltage. The USB-C specification prohibits changing Vbus voltage, which is what Qualcomm does to hit its fast charge targets. Now Google is formally changing its best practices that it recommends for Android, and it doesn’t sound like a solution Qualcomm or other quick-charge technology companies will be happy with.
In its new Android Compatibility Guide for Android 7.0 (Nougat), Google states the following:
Type-C devices are STRONGLY RECOMMENDED to not support proprietary charging methods that modify Vbus voltage beyond default levels, or alter sink/source roles as such may result in interoperability issues with the chargers or devices that support the standard USB Power Delivery methods. While this is called out as “STRONGLY RECOMMENDED”, in future Android versions we might REQUIRE all type-C devices to support full interoperability with standard type-C chargers.
No reason has been provided for the change, but it could be related to the general uncertainty we’ve seen in the USB-C market. Right now, you’ve got a great many cables manufactured to particular standards, with all of this poorly communicated to end users. That’s before we even touch the problem of bad cables in and of themselves. It’s entirely possible that Google is taking this step because an improperly constructed cable, combined with a Quick Charge service, can do some significant harm to a device.
What Google is chasing here is the idea of USB-C as a truly universal standard, where the cables all work with all of the devices. We’ve seen more problems here than I honestly anticipated — I don’t remember anyone putting USB 3.0 under the same kind of limelight, but then USB 3.0 wasn’t trying to be all things to all people. The fact that USB-C can tackle everything from HDMI, to peripheral attachments (via Thunderbolt 3) means that the number of parts that can connect to the same port has leapt upwards. But as we discussed yesterday, these cables aren’t always fungible, and the cables that can do everything are significantly more expensive. Users who typically buy the cheapest cables, be warned — that’s not going to work this time around.
Qualcomm has always maintained that its charging is fine and presents no risk to any Android devices, and to be fair, we’ve never heard of any failures. Nonetheless, if Google squashes the standard altogether and starts requiring full compatibility, it could dent the fast-charging market and result in fewer devices being released — at least until someone figures out a different way around the problem that doesn’t require changing the Vbus.